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data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Precious_opal" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Precious_opal"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Precious opal</span> </div> </a> <ul id="toc-Precious_opal-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Common_opal" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Common_opal"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Common opal</span> </div> </a> <ul id="toc-Common_opal-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Varieties_of_common_opal" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Varieties_of_common_opal"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Varieties of common opal</span> </div> </a> <ul id="toc-Varieties_of_common_opal-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-History" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#History"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>History</span> </div> </a> <ul id="toc-History-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Sources" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Sources"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Sources</span> </div> </a> <button aria-controls="toc-Sources-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Sources subsection</span> </button> <ul id="toc-Sources-sublist" class="vector-toc-list"> <li id="toc-Australia" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Australia"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.1</span> <span>Australia</span> </div> </a> <ul id="toc-Australia-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Ethiopia" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Ethiopia"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.2</span> <span>Ethiopia</span> </div> </a> <ul id="toc-Ethiopia-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Virgin_Valley,_Nevada" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Virgin_Valley,_Nevada"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.3</span> <span>Virgin Valley, Nevada</span> </div> </a> <ul id="toc-Virgin_Valley,_Nevada-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Mexico" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Mexico"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.4</span> <span>Mexico</span> </div> </a> <ul id="toc-Mexico-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Other_locations" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Other_locations"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.5</span> <span>Other locations</span> </div> </a> <ul id="toc-Other_locations-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Fossil_opal" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Fossil_opal"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Fossil opal</span> </div> </a> <ul id="toc-Fossil_opal-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Synthetic_opal" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Synthetic_opal"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Synthetic opal</span> </div> </a> <ul id="toc-Synthetic_opal-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Local_atomic_structure" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Local_atomic_structure"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Local atomic structure</span> </div> </a> <button aria-controls="toc-Local_atomic_structure-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Local atomic structure subsection</span> </button> <ul id="toc-Local_atomic_structure-sublist" class="vector-toc-list"> <li id="toc-Microcrystalline_opal" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Microcrystalline_opal"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.1</span> <span>Microcrystalline opal</span> </div> </a> <ul id="toc-Microcrystalline_opal-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Noncrystalline_opal" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Noncrystalline_opal"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.2</span> <span>Noncrystalline opal</span> </div> </a> <ul id="toc-Noncrystalline_opal-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Opal_surface_chemical_groups" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Opal_surface_chemical_groups"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.3</span> <span>Opal surface chemical groups</span> </div> </a> <ul id="toc-Opal_surface_chemical_groups-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Etymology" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Etymology"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>Etymology</span> </div> </a> <ul id="toc-Etymology-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Historical_superstitions" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Historical_superstitions"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>Historical superstitions</span> </div> </a> <ul id="toc-Historical_superstitions-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Examples" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Examples"> <div class="vector-toc-text"> <span class="vector-toc-numb">11</span> <span>Examples</span> </div> </a> <ul id="toc-Examples-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">12</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">13</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">14</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Opal</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 68 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-68" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">68 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%A3%D9%88%D8%A8%D8%A7%D9%84" title="أوبال – Arabic" lang="ar" hreflang="ar" data-title="أوبال" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Opal" title="Opal – Azerbaijani" lang="az" hreflang="az" data-title="Opal" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%90%D0%BF%D0%B0%D0%BB" title="Апал – Belarusian" lang="be" hreflang="be" data-title="Апал" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-bcl mw-list-item"><a href="https://bcl.wikipedia.org/wiki/Opalo" title="Opalo – Central Bikol" lang="bcl" hreflang="bcl" data-title="Opalo" data-language-autonym="Bikol Central" data-language-local-name="Central Bikol" class="interlanguage-link-target"><span>Bikol Central</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%9E%D0%BF%D0%B0%D0%BB" title="Опал – Bulgarian" lang="bg" hreflang="bg" data-title="Опал" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Opal" title="Opal – Bosnian" lang="bs" hreflang="bs" data-title="Opal" data-language-autonym="Bosanski" data-language-local-name="Bosnian" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/%C3%92pal" title="Òpal – Catalan" lang="ca" hreflang="ca" data-title="Òpal" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%D0%9E%D0%BF%D0%B0%D0%BB" title="Опал – Chuvash" lang="cv" hreflang="cv" data-title="Опал" data-language-autonym="Чӑвашла" data-language-local-name="Chuvash" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Op%C3%A1l" title="Opál – Czech" lang="cs" hreflang="cs" data-title="Opál" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Opal" title="Opal – Danish" lang="da" hreflang="da" data-title="Opal" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Opal" title="Opal – German" lang="de" hreflang="de" data-title="Opal" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Opaal" title="Opaal – Estonian" lang="et" hreflang="et" data-title="Opaal" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%9F%CF%80%CE%AC%CE%BB%CE%B9%CE%BF%CF%82" title="Οπάλιος – Greek" lang="el" hreflang="el" data-title="Οπάλιος" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/%C3%93palo" title="Ópalo – Spanish" lang="es" hreflang="es" data-title="Ópalo" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Opalo" title="Opalo – Esperanto" lang="eo" hreflang="eo" data-title="Opalo" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Opalo" title="Opalo – Basque" lang="eu" hreflang="eu" data-title="Opalo" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%A7%D9%BE%D8%A7%D9%84" title="اپال – Persian" lang="fa" hreflang="fa" data-title="اپال" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Opale" title="Opale – French" lang="fr" hreflang="fr" data-title="Opale" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/%C3%93pal" title="Ópal – Irish" lang="ga" hreflang="ga" data-title="Ópal" data-language-autonym="Gaeilge" data-language-local-name="Irish" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/%C3%93palo" title="Ópalo – Galician" lang="gl" hreflang="gl" data-title="Ópalo" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%8B%A8%EB%B0%B1%EC%84%9D" title="단백석 – Korean" lang="ko" hreflang="ko" data-title="단백석" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D5%95%D5%BA%D5%A1%D5%AC" title="Օպալ – Armenian" lang="hy" hreflang="hy" data-title="Օպալ" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%93%E0%A4%AA%E0%A4%B2" title="ओपल – Hindi" lang="hi" hreflang="hi" data-title="ओपल" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Opal" title="Opal – Croatian" lang="hr" hreflang="hr" data-title="Opal" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-io mw-list-item"><a href="https://io.wikipedia.org/wiki/Opalo" title="Opalo – Ido" lang="io" hreflang="io" data-title="Opalo" data-language-autonym="Ido" data-language-local-name="Ido" class="interlanguage-link-target"><span>Ido</span></a></li><li class="interlanguage-link interwiki-ilo mw-list-item"><a href="https://ilo.wikipedia.org/wiki/%C3%93palo" title="Ópalo – Iloko" lang="ilo" hreflang="ilo" data-title="Ópalo" data-language-autonym="Ilokano" data-language-local-name="Iloko" class="interlanguage-link-target"><span>Ilokano</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Batu_kalimaya" title="Batu kalimaya – Indonesian" lang="id" hreflang="id" data-title="Batu kalimaya" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-iu mw-list-item"><a href="https://iu.wikipedia.org/wiki/%E1%90%86%E1%90%B8%E1%93%AA" title="ᐆᐸᓪ – Inuktitut" lang="iu" hreflang="iu" data-title="ᐆᐸᓪ" data-language-autonym="ᐃᓄᒃᑎᑐᑦ / inuktitut" data-language-local-name="Inuktitut" class="interlanguage-link-target"><span>ᐃᓄᒃᑎᑐᑦ / inuktitut</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/%C3%93pall" title="Ópall – Icelandic" lang="is" hreflang="is" data-title="Ópall" data-language-autonym="Íslenska" data-language-local-name="Icelandic" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Opale" title="Opale – Italian" lang="it" hreflang="it" data-title="Opale" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%90%D7%95%D7%A4%D7%90%D7%9C" title="אופאל – Hebrew" lang="he" hreflang="he" data-title="אופאל" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%9E%D0%BF%D0%B0%D0%BB" title="Опал – Kazakh" lang="kk" hreflang="kk" data-title="Опал" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-ky mw-list-item"><a href="https://ky.wikipedia.org/wiki/%D0%9E%D0%BF%D0%B0%D0%BB" title="Опал – Kyrgyz" lang="ky" hreflang="ky" data-title="Опал" data-language-autonym="Кыргызча" data-language-local-name="Kyrgyz" class="interlanguage-link-target"><span>Кыргызча</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Op%C4%81ls" title="Opāls – Latvian" lang="lv" hreflang="lv" data-title="Opāls" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Opalas" title="Opalas – Lithuanian" lang="lt" hreflang="lt" data-title="Opalas" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Op%C3%A1l" title="Opál – Hungarian" lang="hu" hreflang="hu" data-title="Opál" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-arz mw-list-item"><a href="https://arz.wikipedia.org/wiki/%D8%A7%D9%88%D8%A8%D8%A7%D9%84" title="اوبال – Egyptian Arabic" lang="arz" hreflang="arz" data-title="اوبال" data-language-autonym="مصرى" data-language-local-name="Egyptian Arabic" class="interlanguage-link-target"><span>مصرى</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Baiduri" title="Baiduri – Malay" lang="ms" hreflang="ms" data-title="Baiduri" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-mn mw-list-item"><a href="https://mn.wikipedia.org/wiki/%D0%93%D1%8D%D1%80%D1%8D%D0%BB%D1%82_%D1%87%D0%B8%D0%BC%D1%8D%D0%B4" title="Гэрэлт чимэд – Mongolian" lang="mn" hreflang="mn" data-title="Гэрэлт чимэд" data-language-autonym="Монгол" data-language-local-name="Mongolian" class="interlanguage-link-target"><span>Монгол</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Opaal" title="Opaal – Dutch" lang="nl" hreflang="nl" data-title="Opaal" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%82%AA%E3%83%91%E3%83%BC%E3%83%AB" title="オパール – Japanese" lang="ja" hreflang="ja" data-title="オパール" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Opal" title="Opal – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Opal" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Opal" title="Opal – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Opal" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Opal" title="Opal – Uzbek" lang="uz" hreflang="uz" data-title="Opal" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pnb mw-list-item"><a href="https://pnb.wikipedia.org/wiki/%D8%A7%D9%88%D9%BE%D9%84" title="اوپل – Western Punjabi" lang="pnb" hreflang="pnb" data-title="اوپل" data-language-autonym="پنجابی" data-language-local-name="Western Punjabi" class="interlanguage-link-target"><span>پنجابی</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Opal" title="Opal – Polish" lang="pl" hreflang="pl" data-title="Opal" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Opala" title="Opala – Portuguese" lang="pt" hreflang="pt" data-title="Opala" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Opal" title="Opal – Romanian" lang="ro" hreflang="ro" data-title="Opal" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9E%D0%BF%D0%B0%D0%BB" title="Опал – Russian" lang="ru" hreflang="ru" data-title="Опал" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sah mw-list-item"><a href="https://sah.wikipedia.org/wiki/%D0%9E%D0%BF%D0%B0%D0%B0%D0%BB" title="Опаал – Yakut" lang="sah" hreflang="sah" data-title="Опаал" data-language-autonym="Саха тыла" data-language-local-name="Yakut" class="interlanguage-link-target"><span>Саха тыла</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Opal" title="Opal – Simple English" lang="en-simple" hreflang="en-simple" data-title="Opal" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Op%C3%A1l" title="Opál – Slovak" lang="sk" hreflang="sk" data-title="Opál" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Opal" title="Opal – Slovenian" lang="sl" hreflang="sl" data-title="Opal" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%9E%D0%BF%D0%B0%D0%BB" title="Опал – Serbian" lang="sr" hreflang="sr" data-title="Опал" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Opal" title="Opal – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Opal" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Opaali" title="Opaali – Finnish" lang="fi" hreflang="fi" data-title="Opaali" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Opal" title="Opal – Swedish" lang="sv" hreflang="sv" data-title="Opal" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tl mw-list-item"><a href="https://tl.wikipedia.org/wiki/Opalo" title="Opalo – Tagalog" lang="tl" hreflang="tl" data-title="Opalo" data-language-autonym="Tagalog" data-language-local-name="Tagalog" class="interlanguage-link-target"><span>Tagalog</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%85%E0%AE%AE%E0%AF%81%E0%AE%A4%E0%AE%95%E0%AF%8D%E0%AE%95%E0%AE%B2%E0%AF%8D" title="அமுதக்கல் – Tamil" lang="ta" hreflang="ta" data-title="அமுதக்கல்" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B9%82%E0%B8%AD%E0%B8%9B%E0%B8%AD%E0%B8%A5" title="โอปอล – Thai" lang="th" hreflang="th" data-title="โอปอล" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Opal" title="Opal – Turkish" lang="tr" hreflang="tr" data-title="Opal" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%9E%D0%BF%D0%B0%D0%BB" title="Опал – Ukrainian" lang="uk" hreflang="uk" data-title="Опал" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-ur mw-list-item"><a href="https://ur.wikipedia.org/wiki/%D8%A7%D9%88%D9%BE%D9%84_(%D8%AC%D9%88%D8%A7%DB%81%D8%B1)" title="اوپل (جواہر) – Urdu" lang="ur" hreflang="ur" data-title="اوپل (جواہر)" data-language-autonym="اردو" data-language-local-name="Urdu" class="interlanguage-link-target"><span>اردو</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Opan" title="Opan – Vietnamese" lang="vi" hreflang="vi" data-title="Opan" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-war mw-list-item"><a href="https://war.wikipedia.org/wiki/Opalo" title="Opalo – Waray" lang="war" hreflang="war" data-title="Opalo" data-language-autonym="Winaray" data-language-local-name="Waray" class="interlanguage-link-target"><span>Winaray</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E8%9B%8B%E7%99%BD%E7%9F%B3" title="蛋白石 – Wu" lang="wuu" hreflang="wuu" data-title="蛋白石" data-language-autonym="吴语" data-language-local-name="Wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E8%9B%8B%E7%99%BD%E7%9F%B3" title="蛋白石 – Chinese" lang="zh" hreflang="zh" data-title="蛋白石" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li><li class="interlanguage-link interwiki-kge mw-list-item"><a href="https://kge.wikipedia.org/wiki/Opal" title="Opal – Komering" lang="kge" hreflang="kge" data-title="Opal" data-language-autonym="Kumoring" data-language-local-name="Komering" class="interlanguage-link-target"><span>Kumoring</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q171058#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div 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class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Hydrated amorphous form of silica</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">For the company, see <a href="/wiki/Opel" title="Opel">Opel</a>.</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">For other uses, see <a href="/wiki/Opal_(disambiguation)" class="mw-disambig" title="Opal (disambiguation)">Opal (disambiguation)</a>.</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">"Opals" redirects here. For other uses, see <a href="/wiki/Opals_(disambiguation)" class="mw-disambig" title="Opals (disambiguation)">Opals (disambiguation)</a>.</div> <p class="mw-empty-elt"> </p> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox"><tbody><tr><th colspan="2" class="infobox-above" style="color:black; background-color: #5cc4e7">Opal</th></tr><tr><td colspan="2" class="infobox-image"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Opal-53714.jpg" class="mw-file-description"><img alt="A blue-green section of opal encased inside a light brown rock" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Opal-53714.jpg/220px-Opal-53714.jpg" decoding="async" width="220" height="144" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Opal-53714.jpg/330px-Opal-53714.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Opal-53714.jpg/440px-Opal-53714.jpg 2x" data-file-width="600" data-file-height="392" /></a></span><div class="infobox-caption">A rich seam of iridescent opal encased in matrix</div></td></tr><tr><th colspan="2" class="infobox-header" style="color:black; background-color: #5cc4e7">General</th></tr><tr><th scope="row" class="infobox-label">Category</th><td class="infobox-data"><a href="/wiki/Mineraloid" title="Mineraloid">Mineraloid</a></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Chemical_formula" title="Chemical formula">Formula</a><br /><style data-mw-deduplicate="TemplateStyles:r886047488">.mw-parser-output .nobold{font-weight:normal}</style><span class="nobold">(repeating unit)</span></th><td class="infobox-data"><a href="/wiki/Hydrate" title="Hydrate">Hydrated</a> <a href="/wiki/Silica" class="mw-redirect" title="Silica">silica</a>. SiO<sub>2</sub>·<i>n</i>H<sub>2</sub>O</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/List_of_mineral_symbols" title="List of mineral symbols">IMA symbol</a></th><td class="infobox-data">Opl<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Crystal_system" title="Crystal system">Crystal system</a></th><td class="infobox-data">Amorphous<sup id="cite_ref-GRG_2-0" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th colspan="2" class="infobox-header" style="color:black; background-color: #5cc4e7">Identification</th></tr><tr><th scope="row" class="infobox-label">Color</th><td class="infobox-data">Colorless, white, yellow, red, orange, green, brown, black, blue, pink</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Crystal_habit" title="Crystal habit">Crystal habit</a></th><td class="infobox-data">Irregular veins, in masses, in nodules</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Cleavage_(crystal)" title="Cleavage (crystal)">Cleavage</a></th><td class="infobox-data">None<sup id="cite_ref-GRG_2-1" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Fracture_(mineralogy)" title="Fracture (mineralogy)">Fracture</a></th><td class="infobox-data"><a href="/wiki/Conchoidal" class="mw-redirect" title="Conchoidal">Conchoidal</a> to uneven<sup id="cite_ref-GRG_2-2" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Mohs_scale_of_mineral_hardness" class="mw-redirect" title="Mohs scale of mineral hardness">Mohs scale</a> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886047488"><span class="nobold">hardness</span></th><td class="infobox-data">5.5–6<sup id="cite_ref-GRG_2-3" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Lustre_(mineralogy)" title="Lustre (mineralogy)">Luster</a></th><td class="infobox-data">Subvitreous to waxy<sup id="cite_ref-GRG_2-4" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Streak_(mineralogy)" title="Streak (mineralogy)">Streak</a></th><td class="infobox-data">White</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Transparency_and_translucency" title="Transparency and translucency">Diaphaneity</a></th><td class="infobox-data">opaque, translucent, transparent</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Specific_gravity" class="mw-redirect" title="Specific gravity">Specific gravity</a></th><td class="infobox-data"><span class="nowrap"><span data-sort-value="7000215000000000000♠"></span>2.15<span style="margin-left:0.3em;"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.2em;font-size:85%;text-align:right;">+0.08<br />−0.90</span></span></span><sup id="cite_ref-GRG_2-12" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Density" title="Density">Density</a></th><td class="infobox-data">2.09 g/cm<sup>3</sup></td></tr><tr><th scope="row" class="infobox-label">Polish luster</th><td class="infobox-data">Vitreous to resinous<sup id="cite_ref-GRG_2-5" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label">Optical properties</th><td class="infobox-data">Single refractive, often anomalous double refractive due to strain<sup id="cite_ref-GRG_2-6" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Refractive_index" title="Refractive index">Refractive index</a></th><td class="infobox-data"><span class="nowrap"><span data-sort-value="7000145000000000000♠"></span>1.450<span style="margin-left:0.3em;"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.2em;font-size:85%;text-align:right;">+0.020<br />−0.080</span></span></span><br />Mexican opal may read as low as 1.37, but typically reads 1.42–1.43<sup id="cite_ref-GRG_2-7" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Birefringence" title="Birefringence">Birefringence</a></th><td class="infobox-data">none<sup id="cite_ref-GRG_2-8" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Pleochroism" title="Pleochroism">Pleochroism</a></th><td class="infobox-data">None<sup id="cite_ref-GRG_2-9" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Ultraviolet" title="Ultraviolet">Ultraviolet</a> <a href="/wiki/Fluorescence" title="Fluorescence">fluorescence</a></th><td class="infobox-data">black or white body color: inert to white to moderate light blue, green, or yellow in long and short wave, may also phosphoresce, common opal: inert to strong green or yellowish green in long and short wave, may phosphoresce; fire opal: inert to moderate greenish brown in long and short wave, may phosphoresce<sup id="cite_ref-GRG_2-10" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Absorption_spectroscopy" title="Absorption spectroscopy">Absorption spectra</a></th><td class="infobox-data">green stones: 660 nm, 470 nm cutoff<sup id="cite_ref-GRG_2-11" class="reference"><a href="#cite_note-GRG-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label">Diagnostic features</th><td class="infobox-data">darkening upon heating</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Solubility" title="Solubility">Solubility</a></th><td class="infobox-data">hot <a href="/wiki/Saline_water" title="Saline water">salt water</a>, <a href="/wiki/Base_(chemistry)" title="Base (chemistry)">bases</a>, <a href="/wiki/Methanol" title="Methanol">methanol</a>, <a href="/wiki/Humic_acid" class="mw-redirect" title="Humic acid">humic acid</a>, <a href="/wiki/Hydrofluoric_acid" title="Hydrofluoric acid">hydrofluoric acid</a></td></tr><tr><th scope="row" class="infobox-label">References</th><td class="infobox-data"><sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup></td></tr></tbody></table> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Opale_gisements.jpg" class="mw-file-description"><img alt="A map of the world displaying the countries where opal is most commonly found; Australia, Ethiopia, Brazil, Mexico and the United States of America are highlighted." src="//upload.wikimedia.org/wikipedia/commons/thumb/4/40/Opale_gisements.jpg/220px-Opale_gisements.jpg" decoding="async" width="220" height="145" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/40/Opale_gisements.jpg/330px-Opale_gisements.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/40/Opale_gisements.jpg/440px-Opale_gisements.jpg 2x" data-file-width="2434" data-file-height="1608" /></a><figcaption>Main opal producing countries</figcaption></figure> <p><b>Opal</b> is a <a href="/wiki/Hydrate" title="Hydrate">hydrated</a> <a href="/wiki/Amorphous" class="mw-redirect" title="Amorphous">amorphous</a> form of <a href="/wiki/Silicon_dioxide" title="Silicon dioxide">silica</a> (SiO<sub>2</sub>·<i>n</i>H<sub>2</sub>O); its <a href="/wiki/Water_content" title="Water content">water content</a> may range from 3% to 21% by weight, but is usually between 6% and 10%. Due to the amorphous chemical structure, it is classified as a <a href="/wiki/Mineraloid" title="Mineraloid">mineraloid</a>, unlike <a href="/wiki/Crystal" title="Crystal">crystalline</a> forms of silica, which are considered <a href="/wiki/Mineral" title="Mineral">minerals</a>. It is deposited at a relatively low temperature and may occur in the <a href="/wiki/Fissure" title="Fissure">fissures</a> of almost any kind of <a href="/wiki/Rock_(geology)" title="Rock (geology)">rock</a>, being most commonly found with <a href="/wiki/Limonite" title="Limonite">limonite</a>, <a href="/wiki/Sandstone" title="Sandstone">sandstone</a>, <a href="/wiki/Rhyolite" title="Rhyolite">rhyolite</a>, <a href="/wiki/Marl" title="Marl">marl</a>, and <a href="/wiki/Basalt" title="Basalt">basalt</a>. </p><p>The name <i>opal</i> is believed to be derived from the <a href="/wiki/Sanskrit" title="Sanskrit">Sanskrit</a> word <span title="Sanskrit-language romanization"><i lang="sa-Latn">upala</i></span> (<span lang="sa"><a href="https://en.wiktionary.org/wiki/%E0%A4%89%E0%A4%AA%E0%A4%B2#Sanskrit" class="extiw" title="wikt:उपल">उपल</a></span>), which means 'jewel', and later the Greek derivative <span title="Ancient Greek (to 1453)-language romanization"><i lang="grc-Latn">opállios</i></span> (<span lang="grc"><a href="https://en.wiktionary.org/wiki/%E1%BD%80%CF%80%CE%AC%CE%BB%CE%BB%CE%B9%CE%BF%CF%82#Ancient_Greek" class="extiw" title="wikt:ὀπάλλιος">ὀπάλλιος</a></span>). </p><p>There are two broad classes of opal: precious and common. Precious opal displays play-of-color (<a href="/wiki/Iridescence" title="Iridescence">iridescence</a>); common opal does not.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> Play-of-color is defined as "a pseudo chromatic optical effect resulting in flashes of colored light from certain minerals, as they are turned in white light."<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> The internal structure of precious opal causes it to <a href="/wiki/Diffraction" title="Diffraction">diffract</a> light, resulting in play-of-color. Depending on the conditions in which it formed, opal may be transparent, translucent, or opaque, and the background color may be white, black, or nearly any color of the visual spectrum. Black opal is considered the rarest, while white, gray, and green opals are the most common. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Precious_opal">Precious opal <span class="anchor" id="Precious_opal_anchor"></span></h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=1" title="Edit section: Precious opal"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Opal_molecular_structure2.jpg" class="mw-file-description"><img alt="A diagram of an opal's molecular structure, showing small lilac spheres packed in misaligned sheets on top of each other. The legend shows that one sphere has a diameter of 150–300 nanometres." src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Opal_molecular_structure2.jpg/220px-Opal_molecular_structure2.jpg" decoding="async" width="220" height="147" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Opal_molecular_structure2.jpg/330px-Opal_molecular_structure2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Opal_molecular_structure2.jpg/440px-Opal_molecular_structure2.jpg 2x" data-file-width="2252" data-file-height="1502" /></a><figcaption>Precious opal consists of spheres of <a href="/wiki/Silicon_dioxide" title="Silicon dioxide">silica</a> molecules arranged in regular, closely packed planes (idealized diagram).</figcaption></figure> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Coober_Pedy_Opal_2.jpg" class="mw-file-description"><img alt="A small opal held side-on between someone's forefinger and thumb. A small sliver of brown rock is visible at the top, with a larger section of opal below it." src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fb/Coober_Pedy_Opal_2.jpg/220px-Coober_Pedy_Opal_2.jpg" decoding="async" width="220" height="151" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fb/Coober_Pedy_Opal_2.jpg/330px-Coober_Pedy_Opal_2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fb/Coober_Pedy_Opal_2.jpg/440px-Coober_Pedy_Opal_2.jpg 2x" data-file-width="1219" data-file-height="834" /></a><figcaption>This precious rough opal from <a href="/wiki/Coober_Pedy" title="Coober Pedy">Coober Pedy</a>, <a href="/wiki/South_Australia" title="South Australia">South Australia</a>, displays nearly every color of the <a href="/wiki/Visible_spectrum" title="Visible spectrum">visible spectrum</a>.</figcaption></figure> <p>Precious opal shows a variable interplay of internal colors, and though it is a mineraloid, it has an internal structure. At microscopic scales, precious opal is composed of silica spheres some 150–300 nm (5.9<span style="margin:0 .15em 0 .25em">×</span>10<sup>−6</sup>–1.18<span style="margin:0 .15em 0 .25em">×</span>10<sup>−5</sup> in) in diameter in a hexagonal or cubic <a href="/wiki/Close-packing_of_equal_spheres" title="Close-packing of equal spheres">close-packed</a> <a href="/wiki/Crystal_structure" title="Crystal structure">lattice</a>. It was shown by J. V. Sanders in the mid-1960s<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> that these ordered silica spheres produce the internal colors by causing the <a href="/wiki/Interference_(wave_propagation)" class="mw-redirect" title="Interference (wave propagation)">interference</a> and <a href="/wiki/Diffraction" title="Diffraction">diffraction</a> of light passing through the microstructure of the opal.<sup id="cite_ref-Klein_9-0" class="reference"><a href="#cite_note-Klein-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> The regularity of the sizes and the packing of these spheres is a prime determinant of the quality of precious opal. Where the distance between the regularly packed planes of spheres is around half the wavelength of a component of <a href="/wiki/Visible_light" class="mw-redirect" title="Visible light">visible light</a>, the light of that wavelength may be subject to diffraction from the <a href="/wiki/Diffraction_grating" title="Diffraction grating">grating</a> created by the stacked planes. The colors that are observed are determined by the spacing between the planes and the orientation of planes with respect to the incident light. The process can be described by <a href="/wiki/Bragg%27s_law" title="Bragg's law">Bragg's law</a> of diffraction. </p><p>Visible light cannot pass through large thicknesses of the opal. This is the basis of the optical <a href="/wiki/Band_gap" title="Band gap">band gap</a> in a <a href="/wiki/Photonic_crystal" title="Photonic crystal">photonic crystal</a>.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> In addition, microfractures may be filled with secondary silica and form thin <a href="/wiki/Lamella_(materials)" title="Lamella (materials)">lamellae</a> inside the opal during its formation. The term <i><a href="/wiki/Opalescence" title="Opalescence">opalescence</a></i> is commonly used to describe this unique and beautiful phenomenon, which in gemology is termed <i><a href="/wiki/Iridescence" title="Iridescence">play of color</a></i>. In gemology, opalescence is applied to the hazy-milky-<a href="/wiki/Turbidity" title="Turbidity">turbid</a> sheen of common or potch opal which does not show a play of color.<sup class="noprint Inline-Template" style="margin-left:0.1em; white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Please_clarify" title="Wikipedia:Please clarify"><span title="this sentence appears to contradict the previous one (April 2022)">clarification needed</span></a></i>]</sup> Opalescence is a form of <a href="/wiki/Adularescence" title="Adularescence">adularescence</a>. </p><p>For gemstone use, most opal is cut and polished to form a <a href="/wiki/Cabochon" title="Cabochon">cabochon</a>. "Natural" opal refers to polished stones consisting wholly of precious opal. Opals too thin to produce a "natural" opal may be combined with other materials to form "composite" gems. An opal <a href="/wiki/Doublet_(lapidary)" title="Doublet (lapidary)">doublet</a> consists of a relatively thin layer of precious opal, backed by a layer of dark-colored material, most commonly ironstone, dark or black common opal (potch), onyx, or obsidian. The darker backing emphasizes the play of color and results in a more attractive display than a lighter potch. An opal triplet is similar to a doublet but has a third layer, a domed cap of clear <a href="/wiki/Quartz" title="Quartz">quartz</a> or plastic on the top. The cap takes a high polish and acts as a protective layer for the opal. The top layer also acts as a magnifier, to emphasize the play of color of the opal beneath, which is often an inferior specimen or an extremely thin section of precious opal. Triplet opals tend to have a more artificial appearance and are not classed as precious gemstones, but rather "composite" gemstones. Jewelry applications of precious opal can be somewhat limited by opal's sensitivity to heat due primarily to its relatively high water content and predisposition to scratching.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> Combined with modern techniques of polishing, a doublet opal can produce a similar effect to Natural black or boulder opal at a fraction of the price. Doublet opal also has the added benefit of having genuine opal as the top visible and touchable layer, unlike triplet opals. </p> <div class="mw-heading mw-heading2"><h2 id="Common_opal">Common opal</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=2" title="Edit section: Common opal"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Common_Rough_Opal.jpg" class="mw-file-description"><img alt="A rock set on a black background with a scale in millimetres at the bottom edge. It shows a mixture of light brown rock with translucent white rock on the underside." src="//upload.wikimedia.org/wikipedia/commons/thumb/4/42/Common_Rough_Opal.jpg/220px-Common_Rough_Opal.jpg" decoding="async" width="220" height="156" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/42/Common_Rough_Opal.jpg/330px-Common_Rough_Opal.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/42/Common_Rough_Opal.jpg/440px-Common_Rough_Opal.jpg 2x" data-file-width="3736" data-file-height="2648" /></a><figcaption>Common rough opal</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:SLOVAKIAN_OPAL_12.jpg" class="mw-file-description"><img alt="Four opals on a black background. Their opalescence is relatively low, appearing more as translucent blue and white rock than opal proper." src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4d/SLOVAKIAN_OPAL_12.jpg/220px-SLOVAKIAN_OPAL_12.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/4d/SLOVAKIAN_OPAL_12.jpg/330px-SLOVAKIAN_OPAL_12.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/4d/SLOVAKIAN_OPAL_12.jpg/440px-SLOVAKIAN_OPAL_12.jpg 2x" data-file-width="4608" data-file-height="3456" /></a><figcaption>White and blue opal from Slovakia</figcaption></figure> <p>Besides the <a href="/wiki/Gemstone" title="Gemstone">gemstone</a> varieties that show a play of color, the other kinds of common opal include the milk opal, milky bluish to greenish (which can sometimes be of gemstone quality); <a href="/wiki/Resin" title="Resin">resin</a> opal, which is honey-yellow with a resinous luster; wood opal, which is caused by the replacement of the organic material in wood with opal;<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Menilite" title="Menilite">menilite</a>, which is brown or grey; <a href="/wiki/Hyalite" title="Hyalite">hyalite</a>, a colorless glass-clear opal sometimes called Muller's glass; <a href="/wiki/Geyserite" title="Geyserite">geyserite</a>, also called <a href="/wiki/Siliceous_sinter" class="mw-redirect" title="Siliceous sinter">siliceous sinter</a>, deposited around <a href="/wiki/Hot_springs" class="mw-redirect" title="Hot springs">hot springs</a> or <a href="/wiki/Geyser" title="Geyser">geysers</a>; and <a href="/wiki/Diatomaceous_earth" title="Diatomaceous earth">diatomaceous earth</a>, the accumulations of <a href="/wiki/Diatom" title="Diatom">diatom</a> shells or tests. Common opal often displays a hazy-milky-<a href="/wiki/Turbidity" title="Turbidity">turbid</a> sheen from within the stone. In <a href="/wiki/Gemology" title="Gemology">gemology</a>, this optical effect is strictly defined as opalescence which is a form of adularescence. </p> <div class="mw-heading mw-heading2"><h2 id="Varieties_of_common_opal">Varieties of common opal</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=3" title="Edit section: Varieties of common opal"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">"Girasol" redirects here. For the American sunflower, see <a href="/wiki/Jerusalem_artichoke" title="Jerusalem artichoke">Jerusalem artichoke</a>.</div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:10_7cts_Brazilian_Crystal_Opal.jpg" class="mw-file-description"><img alt="A small, white, trapezoid opal held in someone's hand. Its fire is relatively bright, display a number of finely-grained colours throughout." src="//upload.wikimedia.org/wikipedia/commons/thumb/9/95/10_7cts_Brazilian_Crystal_Opal.jpg/220px-10_7cts_Brazilian_Crystal_Opal.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/95/10_7cts_Brazilian_Crystal_Opal.jpg/330px-10_7cts_Brazilian_Crystal_Opal.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/95/10_7cts_Brazilian_Crystal_Opal.jpg/440px-10_7cts_Brazilian_Crystal_Opal.jpg 2x" data-file-width="640" data-file-height="480" /></a><figcaption>Brazilian Precious Opal with patches of brilliant color throughout. The brightness of the fire in opal ranges on a scale of 1 to 5 (with 5 being the brightest)<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup></figcaption></figure> <p>"Girasol opal" is a term sometimes mistakenly and improperly used to refer to fire opals, as well as a type of transparent to semitransparent type milky quartz from Madagascar which displays an asterism, or star effect when cut properly. However, the true girasol opal<sup id="cite_ref-LetsTalk_14-0" class="reference"><a href="#cite_note-LetsTalk-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> is a type of <a href="/wiki/Hyalite" title="Hyalite">hyalite</a> opal that exhibits a bluish glow or sheen that follows the light source around. It is not a play of color as seen in precious opal, but rather an effect from microscopic inclusions. It is also sometimes referred to as water opal, too, when it is from Mexico. The two most notable locations of this type of opal are <a href="/wiki/Oregon" title="Oregon">Oregon</a> and Mexico.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p><p>A Peruvian opal (also called blue opal) is a semi-opaque to opaque blue-green stone found in Peru, which is often cut to include the matrix in the more opaque stones. It does not display a play of color. Blue opal also comes from <a href="/wiki/Oregon" title="Oregon">Oregon</a> and Idaho in the <a href="/wiki/Owyhee_River" title="Owyhee River">Owyhee</a> region, as well as from <a href="/wiki/Nevada" title="Nevada">Nevada</a> around the <a href="/wiki/Virgin_Valley" title="Virgin Valley">Virgin Valley</a>.<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> </p><p>Opal is also formed by <a href="/wiki/Diatom" title="Diatom">diatoms</a>. Diatoms are a form of algae that, when they die, often form layers at the bottoms of lakes, bays, or oceans. Their cell walls are made up of hydrated silicon dioxide which gives them <a href="/wiki/Structural_coloration" title="Structural coloration">structural coloration</a> and therefore the appearance of tiny opals when viewed under a microscope. These cell walls or "tests" form the “grains” for the <a href="/wiki/Diatomaceous_earth" title="Diatomaceous earth">diatomaceous earth</a>. This sedimentary rock is white, opaque, and chalky in texture.<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> Diatomite has multiple industrial uses such as filtering or adsorbing since it has a fine particle size and very porous nature, and gardening to increase water absorption. </p> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=4" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Opal was rare and very valuable in antiquity. In Europe, it was a gem prized by royalty.<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-19" class="reference"><a href="#cite_note-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> Until the opening of vast deposits in Australia in the 19th century the only known source was <span title="Slovak-language text"><span lang="sk" style="font-style: normal;"><a href="/wiki/%C4%8Cervenica" title="Červenica">Červenica</a></span></span> beyond the Roman frontier in <a href="/wiki/Slovakia" title="Slovakia">Slovakia</a>.<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> Opal is the national <a href="/wiki/Gemstone" title="Gemstone">gemstone</a> of Australia.<sup id="cite_ref-21" class="reference"><a href="#cite_note-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Sources">Sources</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=5" title="Edit section: Sources"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Opal_from_Yowah,_Queensland,_Australia_2.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/93/Opal_from_Yowah%2C_Queensland%2C_Australia_2.jpg/220px-Opal_from_Yowah%2C_Queensland%2C_Australia_2.jpg" decoding="async" width="220" height="147" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/93/Opal_from_Yowah%2C_Queensland%2C_Australia_2.jpg/330px-Opal_from_Yowah%2C_Queensland%2C_Australia_2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/93/Opal_from_Yowah%2C_Queensland%2C_Australia_2.jpg/440px-Opal_from_Yowah%2C_Queensland%2C_Australia_2.jpg 2x" data-file-width="2016" data-file-height="1344" /></a><figcaption>Polished opal from <a href="/wiki/Yowah" title="Yowah">Yowah</a> (Yowah Nut<sup id="cite_ref-Yowah_nut_22-0" class="reference"><a href="#cite_note-Yowah_nut-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup>), Queensland</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Boulder_Opal.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/17/Boulder_Opal.jpg/220px-Boulder_Opal.jpg" decoding="async" width="220" height="196" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/17/Boulder_Opal.jpg/330px-Boulder_Opal.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/17/Boulder_Opal.jpg/440px-Boulder_Opal.jpg 2x" data-file-width="1993" data-file-height="1780" /></a><figcaption>Boulder opal, Carisbrooke Station near <a href="/wiki/Winton,_Queensland" title="Winton, Queensland">Winton, Queensland</a></figcaption></figure> <p>The primary sources of opal are Australia and Ethiopia, but because of inconsistent and widely varying accountings of their respective levels of extraction, it is difficult to accurately state what proportion of the global supply of opal comes from either country. Australian opal has been cited as accounting for 95–97% of the world's supply of precious opal,<sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> with the state of <a href="/wiki/South_Australia" title="South Australia">South Australia</a> accounting for 80% of the world's supply.<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup> In 2012, Ethiopian opal production was estimated to be 14,000 kg (31,000 lb) by the United States Geological Survey.<sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> <a href="/wiki/United_States_Geological_Survey" title="United States Geological Survey">USGS</a> data from the same period (2012), reveals Australian opal production to be $41 million.<sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> Because of the units of measurement, it is not possible to directly compare Australian and Ethiopian opal production, but these data and others suggest that the traditional percentages given for Australian opal production may be overstated.<sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> Yet, the validity of data in the USGS report appears to conflict with that of Laurs et al.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (April 2015)">citation needed</span></a></i>]</sup> and Mesfin,<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (April 2015)">citation needed</span></a></i>]</sup> who estimated the 2012 Ethiopian opal output (from <a href="/wiki/Wegeltena" title="Wegeltena">Wegeltena</a>) to be only 750 kg (1,650 lb). </p> <div class="mw-heading mw-heading3"><h3 id="Australia">Australia</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=6" title="Edit section: Australia"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The town of <a href="/wiki/Coober_Pedy" title="Coober Pedy">Coober Pedy</a> in <a href="/wiki/South_Australia" title="South Australia">South Australia</a> is a major source of opal. The world's largest and most valuable gem opal "<a href="/wiki/Olympic_Australis" title="Olympic Australis">Olympic Australis</a>" was found in August 1956 at the "Eight Mile" opal field in Coober Pedy. It weighs 17,000 carats (3.4 kg; 7.5 lb) and is 11 inches (280 mm) long, with a height of <style data-mw-deduplicate="TemplateStyles:r1154941027">.mw-parser-output .frac{white-space:nowrap}.mw-parser-output .frac .num,.mw-parser-output .frac .den{font-size:80%;line-height:0;vertical-align:super}.mw-parser-output .frac .den{vertical-align:sub}.mw-parser-output .sr-only{border:0;clip:rect(0,0,0,0);clip-path:polygon(0px 0px,0px 0px,0px 0px);height:1px;margin:-1px;overflow:hidden;padding:0;position:absolute;width:1px}</style><span class="frac">4<span class="sr-only">+</span><span class="num">3</span>⁄<span class="den">4</span></span> in (120 mm) and a width of <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">4<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span> in (110 mm).<sup id="cite_ref-29" class="reference"><a href="#cite_note-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup> </p><p>The <a href="/wiki/Mintabie,_South_Australia" title="Mintabie, South Australia">Mintabie Opal Field</a> in South Australia located about 250 km (160 mi) northwest of Coober Pedy has also produced large quantities of crystal opal and the rarer black opal. Over the years, it has been sold overseas incorrectly as Coober Pedy opal. The black opal is said to be some of the best examples found in Australia. </p><p><a href="/wiki/Andamooka,_South_Australia" title="Andamooka, South Australia">Andamooka</a> in South Australia is also a major producer of matrix opal, crystal opal, and black opal. Another Australian town, <a href="/wiki/Lightning_Ridge,_New_South_Wales" title="Lightning Ridge, New South Wales">Lightning Ridge</a> in <a href="/wiki/New_South_Wales" title="New South Wales">New South Wales</a>, is the main source of black opal, opal containing a predominantly dark background (dark gray to blue-black displaying the play of color), collected from the <a href="/wiki/Griman_Creek_Formation" title="Griman Creek Formation">Griman Creek Formation</a>.<sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> Boulder opal consists of <a href="/wiki/Concretion" title="Concretion">concretions</a> and fracture fillings in a dark siliceous <a href="/wiki/Ironstone" title="Ironstone">ironstone</a> matrix. It is found sporadically in western Queensland, from Kynuna in the north, to <a href="/wiki/Yowah" title="Yowah">Yowah</a> and <a href="/wiki/Koroit_opal_field" title="Koroit opal field">Koroit</a> in the south.<sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> Its largest quantities are found around <a href="/wiki/Jundah" class="mw-redirect" title="Jundah">Jundah</a> and <a href="/wiki/Quilpie" class="mw-redirect" title="Quilpie">Quilpie</a> in <a href="/wiki/South_West_Queensland" title="South West Queensland">South West Queensland</a>. Australia also has opalized <a href="/wiki/Fossil" title="Fossil">fossil</a> remains, including dinosaur bones in New South Wales<sup id="cite_ref-32" class="reference"><a href="#cite_note-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> and South Australia,<sup id="cite_ref-33" class="reference"><a href="#cite_note-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> and marine creatures in South Australia.<sup id="cite_ref-samuseum.sa.gov.au_34-0" class="reference"><a href="#cite_note-samuseum.sa.gov.au-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Ethiopia">Ethiopia</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=7" title="Edit section: Ethiopia"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><span><video id="mwe_player_0" poster="//upload.wikimedia.org/wikipedia/commons/thumb/6/62/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm/220px--Amazing_Play_of_Color_-_Opal_from_GemSelect..webm.jpg" controls="" preload="none" data-mw-tmh="" class="mw-file-element" width="220" height="124" data-durationhint="35" data-mwtitle="Amazing_Play_of_Color_-_Opal_from_GemSelect..webm" data-mwprovider="wikimediacommons" resource="/wiki/File:Amazing_Play_of_Color_-_Opal_from_GemSelect..webm"><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/6/62/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm.480p.vp9.webm" type="video/webm; codecs="vp9, opus"" data-transcodekey="480p.vp9.webm" data-width="854" data-height="480" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/6/62/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm.720p.vp9.webm" type="video/webm; codecs="vp9, opus"" data-transcodekey="720p.vp9.webm" data-width="1280" data-height="720" /><source src="//upload.wikimedia.org/wikipedia/commons/6/62/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm" type="video/webm; codecs="vp9"" data-width="1280" data-height="720" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/6/62/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm.144p.mjpeg.mov" type="video/quicktime" data-transcodekey="144p.mjpeg.mov" data-width="256" data-height="144" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/6/62/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm.240p.vp9.webm" type="video/webm; codecs="vp9, opus"" data-transcodekey="240p.vp9.webm" data-width="426" data-height="240" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/6/62/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm.360p.vp9.webm" type="video/webm; codecs="vp9, opus"" data-transcodekey="360p.vp9.webm" data-width="640" data-height="360" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/6/62/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm/Amazing_Play_of_Color_-_Opal_from_GemSelect..webm.360p.webm" type="video/webm; codecs="vp8, vorbis"" data-transcodekey="360p.webm" data-width="640" data-height="360" /></video></span><figcaption>Opal from Ethiopia</figcaption></figure><p> It has been reported that Northern African opal was used to make tools as early as 4000 BC.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (August 2020)">citation needed</span></a></i>]</sup> The first published report of gem opal from <a href="/wiki/Ethiopia" title="Ethiopia">Ethiopia</a> appeared in 1994, with the discovery of precious opal in the Menz Gishe District, North Shewa Province.<sup id="cite_ref-35" class="reference"><a href="#cite_note-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> The opal, found mostly in the form of nodules, was of volcanic origin and was found predominantly within weathered layers of <a href="/wiki/Rhyolite" title="Rhyolite">rhyolite</a>.<sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> This Shewa Province opal was mostly dark brown in color and had a tendency to crack. These qualities made it unpopular in the gem trade. In 2008, a new opal deposit was found approximately 180 km north of Shewa Province, near the town of <a href="/wiki/Wegeltena" title="Wegeltena">Wegeltena</a>, in Ethiopia's <a href="/wiki/Wollo_Province" title="Wollo Province">Wollo Province</a>. The Wollo Province opal was different from the previous Ethiopian opal finds in that it more closely resembled the sedimentary opals of Australia and Brazil, with a light background and often vivid play-of-color.<sup id="cite_ref-37" class="reference"><a href="#cite_note-37"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup> Wollo Province opal, more commonly referred to as "Welo" or "Wello" opal, has become the dominant Ethiopian opal in the gem trade.<sup id="cite_ref-38" class="reference"><a href="#cite_note-38"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup></p><figure class="mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Jupiter_20_Opal_and_Diamond_Pendant.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e4/Jupiter_20_Opal_and_Diamond_Pendant.jpg/200px-Jupiter_20_Opal_and_Diamond_Pendant.jpg" decoding="async" width="200" height="330" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e4/Jupiter_20_Opal_and_Diamond_Pendant.jpg/300px-Jupiter_20_Opal_and_Diamond_Pendant.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e4/Jupiter_20_Opal_and_Diamond_Pendant.jpg/400px-Jupiter_20_Opal_and_Diamond_Pendant.jpg 2x" data-file-width="2311" data-file-height="3812" /></a><figcaption>Gem grade Ethiopian Welo precious opal pendant</figcaption></figure> <div class="mw-heading mw-heading3"><h3 id="Virgin_Valley,_Nevada"><span id="Virgin_Valley.2C_Nevada"></span>Virgin Valley, Nevada</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=8" title="Edit section: Virgin Valley, Nevada"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Nev_opal09.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/ad/Nev_opal09.jpg/220px-Nev_opal09.jpg" decoding="async" width="220" height="209" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/ad/Nev_opal09.jpg/330px-Nev_opal09.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/ad/Nev_opal09.jpg/440px-Nev_opal09.jpg 2x" data-file-width="558" data-file-height="531" /></a><figcaption>Multicolored rough opal specimen from Virgin Valley, Nevada, US</figcaption></figure> <p>The Virgin Valley<sup id="cite_ref-39" class="reference"><a href="#cite_note-39"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> opal fields of <a href="/wiki/Humboldt_County,_Nevada" title="Humboldt County, Nevada">Humboldt County</a> in northern <a href="/wiki/Nevada" title="Nevada">Nevada</a> produce a wide variety of precious black, crystal, white, fire, and lemon opal. The black fire opal is the official gemstone of Nevada. Most of the precious opal is partial wood replacement. The precious opal is hosted and found <i><a href="/wiki/In_situ#Earth_and_atmospheric_sciences" title="In situ">in situ</a></i> within a subsurface horizon or zone of <a href="/wiki/Bentonite" title="Bentonite">bentonite</a>, which is considered a "lode" deposit. Opals which have weathered out of the <i>in situ</i> deposits are alluvial and considered <a href="/wiki/Placer_deposit" title="Placer deposit">placer deposits</a>. <a href="/wiki/Miocene" title="Miocene">Miocene</a>-age opalised teeth, bones, fish, and a snake head have been found. Some of the opal has high water content and may desiccate and crack when dried. The largest producing mines of Virgin Valley have been the famous Rainbow Ridge,<sup id="cite_ref-40" class="reference"><a href="#cite_note-40"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup> Royal Peacock,<sup id="cite_ref-41" class="reference"><a href="#cite_note-41"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> Bonanza,<sup id="cite_ref-42" class="reference"><a href="#cite_note-42"><span class="cite-bracket">[</span>42<span class="cite-bracket">]</span></a></sup> Opal Queen,<sup id="cite_ref-43" class="reference"><a href="#cite_note-43"><span class="cite-bracket">[</span>43<span class="cite-bracket">]</span></a></sup> and WRT Stonetree/Black Beauty<sup id="cite_ref-44" class="reference"><a href="#cite_note-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup> mines. The largest unpolished black opal in the Smithsonian Institution, known as the "Roebling opal",<sup id="cite_ref-45" class="reference"><a href="#cite_note-45"><span class="cite-bracket">[</span>45<span class="cite-bracket">]</span></a></sup> came out of the tunneled portion of the Rainbow Ridge Mine in 1917, and weighs 2,585 carats (517.0 g; 18.24 oz). The largest polished black opal in the <a href="/wiki/Smithsonian_Institution" title="Smithsonian Institution">Smithsonian Institution</a> comes from the Royal Peacock opal mine in the Virgin Valley, weighing 160 carats (32 g; 1.1 oz), known as the "Black Peacock".<sup id="cite_ref-46" class="reference"><a href="#cite_note-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Mexico">Mexico</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=9" title="Edit section: Mexico"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div><p> Fire opal is a transparent to translucent opal with warm body colors of yellow to orange to red. Although fire opals don't usually show any play of color, they occasionally exhibit bright green flashes. The most famous source of fire opals is the state of <a href="/wiki/Quer%C3%A9taro" title="Querétaro">Querétaro</a> in Mexico; these opals are commonly called Mexican fire opals.<sup id="cite_ref-47" class="reference"><a href="#cite_note-47"><span class="cite-bracket">[</span>47<span class="cite-bracket">]</span></a></sup> Fire opals that do not show a play of color are sometimes referred to as jelly opals. Mexican opals are sometimes cut in their rhyolitic host material if it is hard enough to allow cutting and polishing. This type of Mexican opal is referred to as a Cantera opal. Another type of opal from Mexico, referred to as Mexican water opal, is a colorless opal that exhibits either a bluish or golden internal sheen.<sup id="cite_ref-LetsTalk_14-1" class="reference"><a href="#cite_note-LetsTalk-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup></p><figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Precious_Mexican_Fire_Opal_with_attached_matrix.jpg" class="mw-file-description"><img alt="A specimen of recently mined Precious Mexican Fire Opal. The background host rock (matrix) has characteristic pink-white coloration." src="//upload.wikimedia.org/wikipedia/commons/thumb/4/48/Precious_Mexican_Fire_Opal_with_attached_matrix.jpg/220px-Precious_Mexican_Fire_Opal_with_attached_matrix.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/48/Precious_Mexican_Fire_Opal_with_attached_matrix.jpg/330px-Precious_Mexican_Fire_Opal_with_attached_matrix.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/48/Precious_Mexican_Fire_Opal_with_attached_matrix.jpg/440px-Precious_Mexican_Fire_Opal_with_attached_matrix.jpg 2x" data-file-width="4000" data-file-height="3000" /></a><figcaption>Precious Mexican Fire Opal has bright green and yellow patches (play of color) with an orange-red background typical of Fire Opal.</figcaption></figure> <p>Opal occurs in significant quantity and variety in central Mexico, where <a href="/wiki/Mining" title="Mining">mining</a> and production first originated in the state of <a href="/wiki/Quer%C3%A9taro" title="Querétaro">Querétaro</a>. In this region the opal deposits are located mainly in the mountain ranges of three municipalities: <a href="/wiki/Col%C3%B3n,_Quer%C3%A9taro" title="Colón, Querétaro">Colón</a>, <a href="/wiki/Tequisquiapan" title="Tequisquiapan">Tequisquiapan</a>, and <a href="/wiki/Ezequiel_Montes" class="mw-redirect" title="Ezequiel Montes">Ezequiel Montes</a>. During the 1960s through to the mid-1970s, the Querétaro mines were heavily mined. Today's opal miners report that it was much easier to find quality opals with a lot of fire and play of color back then, whereas today the gem-quality opals are very hard to come by and command hundreds of US dollars or more. The orange-red background color is characteristic of all "fire opals," including "Mexican fire opal". </p><p>The oldest mine in Querétaro is Santa Maria del Iris. This mine was opened around 1870 and has been reopened at least 28 times since. At the moment there are about 100 mines in the regions around Querétaro, but most of them are now closed. The best quality of opals came from the mine Santa Maria del Iris, followed by La Hacienda la Esperanza, Fuentezuelas, La Carbonera, and La Trinidad. Important deposits in the state of <a href="/wiki/Jalisco" title="Jalisco">Jalisco</a> were not discovered until the late 1950s. </p><p>In 1957, Alfonso Ramirez (of Querétaro) accidentally discovered the first opal mine in Jalisco: La Unica, located on the outer area of the volcano of Tequila, near the Huitzicilapan farm in <a href="/wiki/Magdalena,_Jalisco" title="Magdalena, Jalisco">Magdalena</a>. By 1960 there were around 500 known opal mines in this region alone. Other regions of the country that also produce opals (of lesser quality) are <a href="/wiki/Guerrero" title="Guerrero">Guerrero</a>, which produces an opaque opal similar to the opals from Australia (some of these opals are carefully treated with heat to improve their colors so high-quality opals from this area may be suspect). There are also some small opal mines in <a href="/wiki/Morelos" title="Morelos">Morelos</a>, <a href="/wiki/Durango" title="Durango">Durango</a>, <a href="/wiki/Chihuahua_(state)" title="Chihuahua (state)">Chihuahua</a>, <a href="/wiki/Baja_California" title="Baja California">Baja California</a>, <a href="/wiki/Guanajuato" title="Guanajuato">Guanajuato</a>, <a href="/wiki/Puebla" title="Puebla">Puebla</a>, <a href="/wiki/Michoac%C3%A1n" title="Michoacán">Michoacán</a>, and <a href="/wiki/Estado_de_M%C3%A9xico" class="mw-redirect" title="Estado de México">Estado de México</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Other_locations">Other locations</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=10" title="Edit section: Other locations"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:62cts_Brazilian_Crystal_Opal.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/01/62cts_Brazilian_Crystal_Opal.JPG/220px-62cts_Brazilian_Crystal_Opal.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/01/62cts_Brazilian_Crystal_Opal.JPG/330px-62cts_Brazilian_Crystal_Opal.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/01/62cts_Brazilian_Crystal_Opal.JPG/440px-62cts_Brazilian_Crystal_Opal.JPG 2x" data-file-width="2272" data-file-height="1704" /></a><figcaption>Brazilian opal</figcaption></figure> <p>Another source of white base opal or creamy opal in the United States is <a href="/wiki/Spencer,_Idaho" title="Spencer, Idaho">Spencer, Idaho</a>.<sup id="cite_ref-48" class="reference"><a href="#cite_note-48"><span class="cite-bracket">[</span>48<span class="cite-bracket">]</span></a></sup> A high percentage of the opal found there occurs in thin layers. </p><p>Other significant deposits of precious opal around the world can be found in the Czech Republic, Canada, Slovakia, Hungary, Turkey, Indonesia, Brazil (in <a href="/wiki/Pedro_II,_Piau%C3%AD" title="Pedro II, Piauí">Pedro II, Piauí</a><sup id="cite_ref-49" class="reference"><a href="#cite_note-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup>), Honduras (more precisely in <a href="/wiki/Erandique" title="Erandique">Erandique</a>), Guatemala, and Nicaragua. </p><p>In late 2008, <a href="/wiki/NASA" title="NASA">NASA</a> announced the discovery of opal deposits on <a href="/wiki/Mars" title="Mars">Mars</a>.<sup id="cite_ref-50" class="reference"><a href="#cite_note-50"><span class="cite-bracket">[</span>50<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Fossil_opal">Fossil opal</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=11" title="Edit section: Fossil opal"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Opal-44685.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/d5/Opal-44685.jpg/220px-Opal-44685.jpg" decoding="async" width="220" height="177" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/d5/Opal-44685.jpg/330px-Opal-44685.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/d5/Opal-44685.jpg/440px-Opal-44685.jpg 2x" data-file-width="600" data-file-height="483" /></a><figcaption>Wood opal</figcaption></figure> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Opalised_Ichthyosaur_backbone.jpg" class="mw-file-description"><img alt="A museum display of the backbone of an ichthyosaur. The display explains that the ichthyosaur's backbone was eroded, and that opal replaced it, creating a cast of the backbone." src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0e/Opalised_Ichthyosaur_backbone.jpg/220px-Opalised_Ichthyosaur_backbone.jpg" decoding="async" width="220" height="68" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0e/Opalised_Ichthyosaur_backbone.jpg/330px-Opalised_Ichthyosaur_backbone.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0e/Opalised_Ichthyosaur_backbone.jpg/440px-Opalised_Ichthyosaur_backbone.jpg 2x" data-file-width="3974" data-file-height="1227" /></a><figcaption>Precious opal replacing <a href="/wiki/Ichthyosaur" class="mw-redirect" title="Ichthyosaur">ichthyosaur</a> backbone, as a display specimen in <a href="/wiki/South_Australian_Museum" title="South Australian Museum">South Australian Museum</a></figcaption></figure> <p><b>Wood opal</b>, also known as <b>xylopal</b>,<sup id="cite_ref-51" class="reference"><a href="#cite_note-51"><span class="cite-bracket">[</span>51<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-52" class="reference"><a href="#cite_note-52"><span class="cite-bracket">[</span>52<span class="cite-bracket">]</span></a></sup> is a form of opal,<sup id="cite_ref-53" class="reference"><a href="#cite_note-53"><span class="cite-bracket">[</span>53<span class="cite-bracket">]</span></a></sup> as well as a type of <a href="/wiki/Petrified_wood" title="Petrified wood">petrified wood</a> which has developed an opalescent sheen or, more rarely, where the wood has been completely replaced by opal. Other names for this opalized sheen-like wood are <b>opalized wood</b> and <b>opalized petrified wood</b>. It is often used as a <a href="/wiki/Gemstone" title="Gemstone">gemstone</a>.<sup id="cite_ref-54" class="reference"><a href="#cite_note-54"><span class="cite-bracket">[</span>54<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Synthetic_opal">Synthetic opal</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=12" title="Edit section: Synthetic opal"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Colloid_lithography,_artificial_opal,_polystyrene.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/7f/Colloid_lithography%2C_artificial_opal%2C_polystyrene.jpg/220px-Colloid_lithography%2C_artificial_opal%2C_polystyrene.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/7f/Colloid_lithography%2C_artificial_opal%2C_polystyrene.jpg/330px-Colloid_lithography%2C_artificial_opal%2C_polystyrene.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7f/Colloid_lithography%2C_artificial_opal%2C_polystyrene.jpg/440px-Colloid_lithography%2C_artificial_opal%2C_polystyrene.jpg 2x" data-file-width="2880" data-file-height="2160" /></a><figcaption>Artificial opal (made by drying a monodisperse sub-micrometer polystyrene sphere <a href="/wiki/Sol_(colloid)" title="Sol (colloid)">sol</a>) viewed by darkfield optical microscopy</figcaption></figure> <p>Opals of all varieties have been synthesized experimentally and commercially. The discovery of the ordered sphere structure of precious opal led to its synthesis by Pierre Gilson in 1974.<sup id="cite_ref-Klein_9-1" class="reference"><a href="#cite_note-Klein-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> The resulting material is distinguishable from natural opal by its regularity; under magnification, the patches of color are seen to be arranged in a "lizard skin" or "chicken wire" pattern. Furthermore, synthetic opals do not <a href="/wiki/Fluorescence" title="Fluorescence">fluoresce</a> under <a href="/wiki/Ultraviolet" title="Ultraviolet">ultraviolet</a> light. Synthetics are also generally lower in density and are often highly porous. </p><p>Opals which have been created in a laboratory are often termed "lab-created opals", which, while classifiable as man-made and synthetic, are very different from their resin-based counterparts which are also considered man-made and synthetic. The term "synthetic" implies that a stone has been created to be chemically and structurally indistinguishable from a genuine one, and genuine opal contains no resins or polymers. The finest modern lab-created opals do not exhibit the lizard skin or columnar patterning of earlier lab-created varieties, and their patterns are non-directional. They can still be distinguished from genuine opals, however, by their lack of <a href="/wiki/Inclusion_(mineral)" title="Inclusion (mineral)">inclusions</a> and the absence of any surrounding non-opal <a href="/wiki/Matrix_(geology)" title="Matrix (geology)">matrix</a>. While many genuine opals are cut and polished without a matrix, the presence of irregularities in their play-of-color continues to mark them as distinct from even the best lab-created synthetics. </p><p>Other research in macroporous structures have yielded highly ordered materials that have similar optical properties to opals and have been used in cosmetics.<sup id="cite_ref-55" class="reference"><a href="#cite_note-55"><span class="cite-bracket">[</span>55<span class="cite-bracket">]</span></a></sup> Synthetic opals are also deeply investigated in <a href="/wiki/Photonics" title="Photonics">photonics</a> for sensing and light management purposes.<sup id="cite_ref-56" class="reference"><a href="#cite_note-56"><span class="cite-bracket">[</span>56<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-57" class="reference"><a href="#cite_note-57"><span class="cite-bracket">[</span>57<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Local_atomic_structure">Local atomic structure</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=13" title="Edit section: Local atomic structure"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Alphacrist.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/13/Alphacrist.png/220px-Alphacrist.png" decoding="async" width="220" height="211" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/13/Alphacrist.png/330px-Alphacrist.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/13/Alphacrist.png/440px-Alphacrist.png 2x" data-file-width="964" data-file-height="926" /></a><figcaption>The crystal structure of crystalline α-<a href="/wiki/Cristobalite" title="Cristobalite">cristobalite</a>. Locally, the structures of some opals, opal-C, are similar to this.</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Lussatite-France.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Lussatite-France.jpg/220px-Lussatite-France.jpg" decoding="async" width="220" height="174" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Lussatite-France.jpg/330px-Lussatite-France.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Lussatite-France.jpg/440px-Lussatite-France.jpg 2x" data-file-width="3454" data-file-height="2733" /></a><figcaption>Lussatite (opal-CT)</figcaption></figure> <p>The lattice of spheres of opal that cause interference with light is several hundred times larger than the fundamental structure of crystalline silica. As a <a href="/wiki/Mineraloid" title="Mineraloid">mineraloid</a>, no <a href="/wiki/Unit_cell" title="Unit cell">unit cell</a> describes the structure of opal. Nevertheless, opals can be roughly divided into those that show no signs of crystalline order (<a href="/wiki/Amorphous" class="mw-redirect" title="Amorphous">amorphous</a> opal) and those that show signs of the beginning of crystalline order, commonly termed <a href="/wiki/Cryptocrystalline" title="Cryptocrystalline">cryptocrystalline</a> or microcrystalline opal.<sup id="cite_ref-58" class="reference"><a href="#cite_note-58"><span class="cite-bracket">[</span>58<span class="cite-bracket">]</span></a></sup> Dehydration experiments and <a href="/wiki/Infrared_spectroscopy" title="Infrared spectroscopy">infrared spectroscopy</a> have shown that most of the H<sub>2</sub>O in the formula of SiO<sub>2</sub>·<i>n</i>H<sub>2</sub>O of opals is present in the familiar form of clusters of molecular water. Isolated water molecules, and <a href="/wiki/Silanol" title="Silanol">silanols</a>, structures such as SiOH, generally form a lesser proportion of the total and can reside near the surface or in defects inside the opal. </p><p>The structure of low-pressure <a href="/wiki/Polymorphism_(materials_science)" class="mw-redirect" title="Polymorphism (materials science)">polymorphs</a> of anhydrous <a href="/wiki/Silica" class="mw-redirect" title="Silica">silica</a> consists of frameworks of fully corner bonded tetrahedra of SiO<sub>4</sub>. The higher temperature polymorphs of silica <a href="/wiki/Cristobalite" title="Cristobalite">cristobalite</a> and <a href="/wiki/Tridymite" title="Tridymite">tridymite</a> are frequently the first to crystallize from amorphous anhydrous silica, and the local structures of microcrystalline opals also appear to be closer to that of cristobalite and tridymite than to quartz. The structures of tridymite and cristobalite are closely related and can be described as <a href="/wiki/Hexagonal_close_packing" class="mw-redirect" title="Hexagonal close packing">hexagonal</a> and <a href="/wiki/Cubic_close_packing" class="mw-redirect" title="Cubic close packing">cubic close-packed</a> layers. It is therefore possible to have intermediate structures in which the layers are not regularly stacked. </p> <div class="mw-heading mw-heading3"><h3 id="Microcrystalline_opal">Microcrystalline opal</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=14" title="Edit section: Microcrystalline opal"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Microcrystalline opal or <i>Opal-CT</i> has been interpreted as consisting of clusters of stacked <a href="/wiki/Cristobalite" title="Cristobalite">cristobalite</a> and <a href="/wiki/Tridymite" title="Tridymite">tridymite</a> over very short length scales. The spheres of opal in microcrystalline opal are themselves made up of tiny nanocrystalline blades of cristobalite and tridymite. Microcrystalline opal has occasionally been further subdivided in the literature. Water content may be as high as 10 wt%.<sup id="cite_ref-59" class="reference"><a href="#cite_note-59"><span class="cite-bracket">[</span>59<span class="cite-bracket">]</span></a></sup> Opal-CT, also called <i>lussatine</i> or <i>lussatite</i>, is interpreted as consisting of localized order of α-cristobalite with a lot of stacking disorder. Typical water content is about 1.5 wt%. </p> <div class="mw-heading mw-heading3"><h3 id="Noncrystalline_opal">Noncrystalline opal</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=15" title="Edit section: Noncrystalline opal"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Two broad categories of noncrystalline opals, sometimes just referred to as "opal-A" ("A" stands for "amorphous"),<sup id="cite_ref-60" class="reference"><a href="#cite_note-60"><span class="cite-bracket">[</span>60<span class="cite-bracket">]</span></a></sup> have been proposed. The first of these is opal-AG consisting of aggregated spheres of silica, with water filling the space in between. Precious opal and potch opal are generally varieties of this, the difference being in the regularity of the sizes of the spheres and their packing. The second "opal-A" is opal-AN or water-containing amorphous silica-glass. <a href="/wiki/Hyalite" title="Hyalite">Hyalite</a> is another name for this. </p><p>Noncrystalline silica in siliceous sediments is reported to gradually transform to opal-CT and then opal-C as a result of <a href="/wiki/Diagenesis" title="Diagenesis">diagenesis</a>, due to the increasing overburden pressure in <a href="/wiki/Sedimentary" class="mw-redirect" title="Sedimentary">sedimentary</a> rocks, as some of the stacking disorder is removed.<sup id="cite_ref-61" class="reference"><a href="#cite_note-61"><span class="cite-bracket">[</span>61<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-default-size mw-halign-center" typeof="mw:File/Thumb"><a href="/wiki/File:Schematic_silica_gel_surface.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Schematic_silica_gel_surface.png/660px-Schematic_silica_gel_surface.png" decoding="async" width="660" height="167" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Schematic_silica_gel_surface.png/990px-Schematic_silica_gel_surface.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Schematic_silica_gel_surface.png/1320px-Schematic_silica_gel_surface.png 2x" data-file-width="2680" data-file-height="677" /></a><figcaption>Schematic representation of the hydrated opal surface.</figcaption></figure> <div class="mw-heading mw-heading3"><h3 id="Opal_surface_chemical_groups">Opal surface chemical groups</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=16" title="Edit section: Opal surface chemical groups"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The surface of opal in contact with water is covered by <a href="/wiki/Siloxane" title="Siloxane">siloxane</a> bonds (≡Si–O–Si≡) and <a href="/wiki/Silanol" title="Silanol">silanol</a> groups (≡Si–OH). This makes the opal surface very <a href="/wiki/Hydrophile" title="Hydrophile">hydrophilic</a> and capable of forming numerous <a href="/wiki/Hydrogen_bond" title="Hydrogen bond">hydrogen bonds</a>. </p> <div class="mw-heading mw-heading2"><h2 id="Etymology">Etymology</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=17" title="Edit section: Etymology"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The word 'opal' is adapted from the <a href="/wiki/Latin" title="Latin">Latin</a> term <span title="Latin-language text"><i lang="la">opalus</i></span>. The origin of this word in turn is a matter of debate, but most modern references suggest it is adapted from the <a href="/wiki/Sanskrit" title="Sanskrit">Sanskrit</a> word <span title="Sanskrit-language text"><i lang="sa-Latn">úpala</i></span> meaning ‘precious stone’.<sup id="cite_ref-eckert_62-0" class="reference"><a href="#cite_note-eckert-62"><span class="cite-bracket">[</span>62<span class="cite-bracket">]</span></a></sup> </p><p>As references to the gem are made by <a href="/wiki/Pliny_the_Elder" title="Pliny the Elder">Pliny the Elder</a>, one theory attributed the name's origin to Roman mythology: to have been adapted from <a href="/wiki/Ops" title="Ops">Ops</a>, the wife of <a href="/wiki/Saturn_(mythology)" title="Saturn (mythology)">Saturn</a>, and goddess of fertility. (The portion of <a href="/wiki/Saturnalia" title="Saturnalia">Saturnalia</a> devoted to Ops was "Opalia", similar to <span title="Latin-language text"><i lang="la">opalus</i></span>.) </p><p>Another common claim was that the term was adapted from the <a href="/wiki/Ancient_Greek_language" class="mw-redirect" title="Ancient Greek language">Ancient Greek</a> word, <span title="Ancient Greek (to 1453)-language text"><i lang="grc-Latn">opallios</i></span>. This word has two meanings, one is related to "seeing" and forms the basis of the English words like "opaque"; the other is "other" as in "alias" and "alter". It is claimed that <span title="Latin-language text"><i lang="la">opalus</i></span> combined these uses, meaning "to see a change in color". However, historians have noted the first appearances of <span title="Ancient Greek (to 1453)-language text"><i lang="grc-Latn">opallios</i></span> do not occur until after the Romans had taken over the Greek states in 180 BC and they had previously used the term <span title="Ancient Greek (to 1453)-language text"><i lang="grc-Latn">paederos</i></span>.<sup id="cite_ref-eckert_62-1" class="reference"><a href="#cite_note-eckert-62"><span class="cite-bracket">[</span>62<span class="cite-bracket">]</span></a></sup> </p><p>However, the argument for the Sanskrit origin is strong. The term first appears in Roman references around 250 BC, at a time when the opal was valued above all other gems. The opals were supplied by traders from the <a href="/wiki/Bosporus" title="Bosporus">Bosporus</a>, who claimed the gems were being supplied from India. Before this, the stone was referred to by a variety of names, but these fell from use after 250 BC. </p> <div class="mw-heading mw-heading2"><h2 id="Historical_superstitions">Historical superstitions</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=18" title="Edit section: Historical superstitions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In the Middle Ages, opal was considered a stone that could provide great luck because it was believed to possess all the virtues of each gemstone whose color was represented in the color spectrum of the opal.<sup id="cite_ref-Fernie_63-0" class="reference"><a href="#cite_note-Fernie-63"><span class="cite-bracket">[</span>63<span class="cite-bracket">]</span></a></sup> It was also said to grant invisibility if wrapped in a fresh <a href="/wiki/Bay_leaf" title="Bay leaf">bay leaf</a> and held in the hand.<sup id="cite_ref-Fernie_63-1" class="reference"><a href="#cite_note-Fernie-63"><span class="cite-bracket">[</span>63<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-64" class="reference"><a href="#cite_note-64"><span class="cite-bracket">[</span>64<span class="cite-bracket">]</span></a></sup> As a result, the opal was seen as the patron gemstone for <a href="/wiki/Thieves" class="mw-redirect" title="Thieves">thieves</a> during the <a href="/wiki/Medieval_period" class="mw-redirect" title="Medieval period">medieval period</a>.<sup id="cite_ref-65" class="reference"><a href="#cite_note-65"><span class="cite-bracket">[</span>65<span class="cite-bracket">]</span></a></sup> Following the publication of Sir <a href="/wiki/Walter_Scott" title="Walter Scott">Walter Scott</a>'s <i><a href="/wiki/Anne_of_Geierstein" title="Anne of Geierstein">Anne of Geierstein</a></i> in 1829, opal acquired a less auspicious reputation. In Scott's novel, the Baroness of Arnheim wears an opal <a href="/wiki/Amulet" title="Amulet">talisman</a> with supernatural powers. When a drop of <a href="/wiki/Holy_water" title="Holy water">holy water</a> falls on the talisman, the opal turns into a colorless stone and the Baroness dies soon thereafter. Due to the popularity of Scott's novel, people began to associate opals with bad luck and death.<sup id="cite_ref-Fernie_63-2" class="reference"><a href="#cite_note-Fernie-63"><span class="cite-bracket">[</span>63<span class="cite-bracket">]</span></a></sup> Within a year of the publishing of Scott's novel in April 1829, the sale of opals in Europe dropped by 50%, and remained low for the next 20 years or so.<sup id="cite_ref-66" class="reference"><a href="#cite_note-66"><span class="cite-bracket">[</span>66<span class="cite-bracket">]</span></a></sup> </p><p>Even as recently as the beginning of the 20th century, it was believed that when a Russian saw an opal among other goods offered for sale, he or she should not buy anything more, as the opal was believed to embody the <a href="/wiki/Evil_eye" title="Evil eye">evil eye</a>.<sup id="cite_ref-Fernie_63-3" class="reference"><a href="#cite_note-Fernie-63"><span class="cite-bracket">[</span>63<span class="cite-bracket">]</span></a></sup> </p><p>Opal is considered the <a href="/wiki/Birthstone" title="Birthstone">birthstone</a> for people born in October.<sup id="cite_ref-67" class="reference"><a href="#cite_note-67"><span class="cite-bracket">[</span>67<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Examples">Examples</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=19" title="Edit section: Examples"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>The <a href="/wiki/Olympic_Australis" title="Olympic Australis">Olympic Australis</a>, the world's largest and most valuable gem opal, found in <a href="/wiki/Coober_Pedy" title="Coober Pedy">Coober Pedy</a><sup id="cite_ref-68" class="reference"><a href="#cite_note-68"><span class="cite-bracket">[</span>68<span class="cite-bracket">]</span></a></sup></li> <li>The <a href="/wiki/Andamooka_Opal" title="Andamooka Opal">Andamooka Opal</a>, presented to <a href="/wiki/Elizabeth_II" title="Elizabeth II">Queen Elizabeth II</a>, also known as the Queen's Opal</li> <li>The <a href="/wiki/South_Australian_Museum#Opal_fossils_at_the_South_Australian_Museum" title="South Australian Museum">Addyman Plesiosaur</a> from Andamooka, "the finest known opalised skeleton on Earth"<sup id="cite_ref-samuseum.sa.gov.au_34-1" class="reference"><a href="#cite_note-samuseum.sa.gov.au-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup></li> <li>The Burning of Troy, the now-lost opal presented to <a href="/wiki/Jos%C3%A9phine_de_Beauharnais" title="Joséphine de Beauharnais">Joséphine de Beauharnais</a> by <a href="/wiki/Napoleon_I_of_France" class="mw-redirect" title="Napoleon I of France">Napoleon I of France</a> and the first named opal<sup id="cite_ref-69" class="reference"><a href="#cite_note-69"><span class="cite-bracket">[</span>69<span class="cite-bracket">]</span></a></sup></li> <li>The <a href="/wiki/Flame_Queen_Opal" title="Flame Queen Opal">Flame Queen Opal</a></li> <li>Opal cameo (jewellery-case) of a profile head of a helmeted warrior, attributed to Wilhelm Schmidt<sup id="cite_ref-70" class="reference"><a href="#cite_note-70"><span class="cite-bracket">[</span>70<span class="cite-bracket">]</span></a></sup></li> <li>The <a href="/wiki/Halley%27s_Comet_Opal" title="Halley's Comet Opal">Halley's Comet Opal</a>, the world's largest uncut black opal</li> <li>Although the clock faces above the information stand in <a href="/wiki/Grand_Central_Terminal" title="Grand Central Terminal">Grand Central Terminal</a> in New York City are often said to be opal, they are in fact <a href="/wiki/Milk_glass" title="Milk glass">opalescent glass</a></li> <li>The Roebling Opal, Smithsonian Institution<sup id="cite_ref-71" class="reference"><a href="#cite_note-71"><span class="cite-bracket">[</span>71<span class="cite-bracket">]</span></a></sup></li> <li>The <a href="/wiki/Galaxy_Opal" title="Galaxy Opal">Galaxy Opal</a>, listed as the "World's Largest Polished Opal" in the 1992 <i>Guinness Book of Records</i><sup id="cite_ref-72" class="reference"><a href="#cite_note-72"><span class="cite-bracket">[</span>72<span class="cite-bracket">]</span></a></sup></li> <li>The Rainbow Virgin, "the finest crystal opal specimen ever unearthed"<sup id="cite_ref-73" class="reference"><a href="#cite_note-73"><span class="cite-bracket">[</span>73<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-74" class="reference"><a href="#cite_note-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-SAM_media_release_17_May_2017_75-0" class="reference"><a href="#cite_note-SAM_media_release_17_May_2017-75"><span class="cite-bracket">[</span>75<span class="cite-bracket">]</span></a></sup></li> <li>The Sea of Opal, the largest black opal in the world<sup id="cite_ref-76" class="reference"><a href="#cite_note-76"><span class="cite-bracket">[</span>76<span class="cite-bracket">]</span></a></sup></li> <li>The <a href="/wiki/Fire_of_Australia_opal" title="Fire of Australia opal">Fire of Australia</a>, assumed to be "the finest uncut opal in existence"<sup id="cite_ref-SAM_media_release_17_May_2017_75-1" class="reference"><a href="#cite_note-SAM_media_release_17_May_2017-75"><span class="cite-bracket">[</span>75<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-77" class="reference"><a href="#cite_note-77"><span class="cite-bracket">[</span>77<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Beverly_the_Bug" title="Beverly the Bug">Beverly the Bug</a>, the first known example of an opal with an insect <a href="/wiki/Inclusion_(mineral)" title="Inclusion (mineral)">inclusion</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=20" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1259569809">.mw-parser-output .portalbox{padding:0;margin:0.5em 0;display:table;box-sizing:border-box;max-width:175px;list-style:none}.mw-parser-output .portalborder{border:1px solid var(--border-color-base,#a2a9b1);padding:0.1em;background:var(--background-color-neutral-subtle,#f8f9fa)}.mw-parser-output .portalbox-entry{display:table-row;font-size:85%;line-height:110%;height:1.9em;font-style:italic;font-weight:bold}.mw-parser-output .portalbox-image{display:table-cell;padding:0.2em;vertical-align:middle;text-align:center}.mw-parser-output .portalbox-link{display:table-cell;padding:0.2em 0.2em 0.2em 0.3em;vertical-align:middle}@media(min-width:720px){.mw-parser-output .portalleft{clear:left;float:left;margin:0.5em 1em 0.5em 0}.mw-parser-output .portalright{clear:right;float:right;margin:0.5em 0 0.5em 1em}}</style><ul role="navigation" aria-label="Portals" class="noprint portalbox portalborder portalright"> <li class="portalbox-entry"><span class="portalbox-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Am%C3%A9thystre_sceptre2.jpg/23px-Am%C3%A9thystre_sceptre2.jpg" decoding="async" width="23" height="28" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Am%C3%A9thystre_sceptre2.jpg/34px-Am%C3%A9thystre_sceptre2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Am%C3%A9thystre_sceptre2.jpg/46px-Am%C3%A9thystre_sceptre2.jpg 2x" data-file-width="2893" data-file-height="3552" /></span></span></span><span class="portalbox-link"><a href="/wiki/Portal:Minerals" title="Portal:Minerals">Minerals portal</a></span></li></ul> <ul><li><a href="/wiki/Biogenic_silica" title="Biogenic silica">Biogenic silica</a></li> <li><a href="/wiki/Cacholong" title="Cacholong">Cacholong</a> – variety of opal<span style="display:none" class="category-wikidata-fallback-annotation">Pages displaying wikidata descriptions as a fallback</span></li> <li><a href="/wiki/Foil_opal" title="Foil opal">Foil opal</a> – metal foil sometimes used to create reflection and sparkle behind milky glass or quartz faces in costume jewelry simulating real opal<span style="display:none" class="category-wikidata-fallback-annotation">Pages displaying wikidata descriptions as a fallback</span></li> <li><a href="/wiki/Labradorite" title="Labradorite">Labradorite</a></li> <li><a href="/wiki/Opalite" title="Opalite">Opalite</a> – Trade name for opal and moonstone simulants</li> <li><a href="/wiki/Optical_phenomena" class="mw-redirect" title="Optical phenomena">Optical phenomena</a> – Observable events that result from the interaction of light and matter<span style="display:none" class="category-annotation-with-redirected-description">Pages displaying short descriptions of redirect targets</span></li> <li><a href="/wiki/Uncut_Gems" title="Uncut Gems"><i>Uncut Gems</i> (2019 film)</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=21" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFWarr2021" class="citation journal cs1">Warr, L.N. 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Retrieved <span class="nowrap">15 May</span> 2018</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.minerals.net&rft.atitle=diatomite+%E2%80%93+The+Mineral+and+Gemstone+Kingdom&rft_id=http%3A%2F%2Fwww.minerals.net%2Fmineral-variety%2Fmineral%2Fdiatomite.aspx&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text">"The central stone on the thirteenth-century crown of the Holy Roman Emperor was an opal said to be the color of pure white snow, sparkling with splashes of bright red wine: it was called "the Orphanus", perhaps because there was no other stone like it.24 And on New Year's Day 1584,25 Queen Elizabeth I was delighted to receive an opal parure—a full set of matching jewelry—from one of her favorite courtiers, Sir Christopher Hatton." Finlay, Victoria. Jewels: A Secret History (Kindle Locations 2145–2148). Random House Publishing Group. Kindle Edition.</span> </li> <li id="cite_note-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-19">^</a></b></span> <span class="reference-text">"All of these early stones were almost certainly from the ancient mines of Slovakia—the same source as Nonius’ precious stone and the Holy Roman Emperor’s red-and-white one. The mines were worked until the late nineteenth century..." Finlay, Victoria. Jewels: A Secret History (Kindle Locations 2163–2165). Random House Publishing Group. Kindle Edition.</span> </li> <li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text">Finlay, Victoria. Jewels: A Secret History (Kindle Location 1871). Random House Publishing Group. Kindle Edition.</span> </li> <li id="cite_note-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-21">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.pmc.gov.au/government/australian-national-symbols/australian-national-gemstone">"Australian National Gemstone"</a>. Australian Government, Department of the Prime Minister and Cabinet<span class="reference-accessdate">. Retrieved <span class="nowrap">10 June</span> 2018</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Australian+National+Gemstone&rft.pub=Australian+Government%2C+Department+of+the+Prime+Minister+and+Cabinet&rft_id=https%3A%2F%2Fwww.pmc.gov.au%2Fgovernment%2Faustralian-national-symbols%2Faustralian-national-gemstone&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-Yowah_nut-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-Yowah_nut_22-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.mindat.org/min-9838.html">"Yowah Nut: Yowah Nut mineral information and data"</a>. <i>Mindat.org</i>. 20 February 2011. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110512015028/http://www.mindat.org/min-9838.html">Archived</a> from the original on 12 May 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">8 March</span> 2011</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Mindat.org&rft.atitle=Yowah+Nut%3A+Yowah+Nut+mineral+information+and+data&rft.date=2011-02-20&rft_id=http%3A%2F%2Fwww.mindat.org%2Fmin-9838.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.itsanhonour.gov.au/symbols/gemstone.cfm">"Gemstone"</a>. <i>It's an Honour</i>. Australian Government. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110129022445/http://www.itsanhonour.gov.au/symbols/gemstone.cfm">Archived</a> from the original on 29 January 2011.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=It%27s+an+Honour&rft.atitle=Gemstone&rft_id=http%3A%2F%2Fwww.itsanhonour.gov.au%2Fsymbols%2Fgemstone.cfm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-24">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.diamonds.net/Magazine/Article.aspx?ArticleID=46032&RDRIssueID=120">"Rapaport Magazine – A Designer Stone"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20141006154330/http://www.diamonds.net/Magazine/Article.aspx?ArticleID=46032&RDRIssueID=120">Archived</a> from the original on 6 October 2014.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Rapaport+Magazine+%E2%80%93+A+Designer+Stone&rft_id=http%3A%2F%2Fwww.diamonds.net%2FMagazine%2FArticle.aspx%3FArticleID%3D46032%26RDRIssueID%3D120&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-25">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20120716230021/http://www.premcab.sa.gov.au/emblems/opals1.htm">"Opal – South Australia's Gemstone"</a>. Government of South Australia. Archived from <a rel="nofollow" class="external text" href="http://www.premcab.sa.gov.au/emblems/opals1.htm">the original</a> on 16 July 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">11 July</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Opal+%E2%80%93+South+Australia%27s+Gemstone&rft.pub=Government+of+South+Australia&rft_id=http%3A%2F%2Fwww.premcab.sa.gov.au%2Femblems%2Fopals1.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-26">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFYager2013" class="citation cs2">Yager, Thomas R. (1 December 2013), "The Mineral Industry of Ethiopia", <a rel="nofollow" class="external text" href="https://minerals.usgs.gov/minerals/pubs/country/2012/myb3-2012-et.pdf"><i>United States Geological Survey, 2012 Minerals Yearbook</i></a> <span class="cs1-format">(PDF)</span>, pp. 17.1–17.5, <a rel="nofollow" class="external text" href="https://web.archive.org/web/20141006150924/http://minerals.usgs.gov/minerals/pubs/country/2012/myb3-2012-et.pdf">archived</a> <span class="cs1-format">(PDF)</span> from the original on 6 October 2014</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=The+Mineral+Industry+of+Ethiopia&rft.btitle=United+States+Geological+Survey%2C+2012+Minerals+Yearbook&rft.pages=17.1-17.5&rft.date=2013-12-01&rft.aulast=Yager&rft.aufirst=Thomas+R.&rft_id=http%3A%2F%2Fminerals.usgs.gov%2Fminerals%2Fpubs%2Fcountry%2F2012%2Fmyb3-2012-et.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-27">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTse2013" class="citation cs2">Tse, Pui-Kwan (1 December 2013), "The Mineral Industry of Australia", <a rel="nofollow" class="external text" href="https://minerals.usgs.gov/minerals/pubs/country/2012/myb3-2012-as.pdf"><i>United States Geological Survey, 2012 Minerals Yearbook</i></a> <span class="cs1-format">(PDF)</span>, pp. 3.1–3.27, <a rel="nofollow" class="external text" href="https://web.archive.org/web/20141006090605/http://minerals.usgs.gov/minerals/pubs/country/2012/myb3-2012-as.pdf">archived</a> <span class="cs1-format">(PDF)</span> from the original on 6 October 2014<span class="reference-accessdate">, retrieved <span class="nowrap">20 September</span> 2014</span></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=The+Mineral+Industry+of+Australia&rft.btitle=United+States+Geological+Survey%2C+2012+Minerals+Yearbook&rft.pages=3.1-3.27&rft.date=2013-12-01&rft.aulast=Tse&rft.aufirst=Pui-Kwan&rft_id=http%3A%2F%2Fminerals.usgs.gov%2Fminerals%2Fpubs%2Fcountry%2F2012%2Fmyb3-2012-as.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-28">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.diamonds.net/Magazine/Article.aspx?ArticleID=38027&RDRIssueID=85">"Rapaport Magazine – Ethiopian Opal"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20141006134901/http://www.diamonds.net/Magazine/Article.aspx?ArticleID=38027&RDRIssueID=85">Archived</a> from the original on 6 October 2014.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Rapaport+Magazine+%E2%80%93+Ethiopian+Opal&rft_id=http%3A%2F%2Fwww.diamonds.net%2FMagazine%2FArticle.aspx%3FArticleID%3D38027%26RDRIssueID%3D85&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-29">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCram2006" class="citation book cs1">Cram, Len (2006). <i>A history of South Australian opal, 1840–2005</i>. 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class="Z3988"></span></span> </li> <li id="cite_note-37"><span class="mw-cite-backlink"><b><a href="#cite_ref-37">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRondeau2010" class="citation journal cs1">Rondeau, Benjamin (Summer 2010). <a rel="nofollow" class="external text" href="https://doi.org/10.5741%2FGEMS.46.2.90">"Play-of-color from Wegeltena, Wollo Province, Ethiopia"</a>. <i>Gems & Gemology</i>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.5741%2FGEMS.46.2.90">10.5741/GEMS.46.2.90</a></span>.</cite><span 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href="https://web.archive.org/web/20140924044930/http://addisfortune.com/Vol_12_No_623_Archive/agenda.htm">Archived</a> from the original on 24 September 2014.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Addis+Fortune&rft.atitle=Opal+Trade+Transforms+North+Wollo&rft.date=2012-04-08&rft.aulast=Gashaw&rft.aufirst=Yidneka&rft_id=http%3A%2F%2Faddisfortune.com%2FVol_12_No_623_Archive%2Fagenda.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-39"><span class="mw-cite-backlink"><b><a href="#cite_ref-39">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.mindat.org/loc-5881.html">"Virgin Valley District, Humboldt Co., Nevada"</a>. <i>mindat.org</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120430090041/http://www.mindat.org/loc-5881.html">Archived</a> from the original on 30 April 2012.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=mindat.org&rft.atitle=Virgin+Valley+District%2C+Humboldt+Co.%2C+Nevada&rft_id=http%3A%2F%2Fwww.mindat.org%2Floc-5881.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-40"><span class="mw-cite-backlink"><b><a href="#cite_ref-40">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.mindat.org/loc-19286.html">"Rainbow Ridge Mine"</a>. <i>mindat.org</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120430115218/http://www.mindat.org/loc-19286.html">Archived</a> from the original on 30 April 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title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=mindat.org&rft.atitle=Bonanza+Opal+Workings+%28Virgin+Opal%29%2C+Virgin+Valley+District%2C+Humboldt+Co.%2C+Nevada&rft_id=http%3A%2F%2Fwww.mindat.org%2Floc-8801.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-43"><span class="mw-cite-backlink"><b><a href="#cite_ref-43">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.mindat.org/loc-213530.html">"Opal Queen group, Virgin Valley District, Humboldt Co., Nevada"</a>. <i>mindat.org</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120430115233/http://www.mindat.org/loc-213530.html">Archived</a> from the original on 30 April 2012.</cite><span 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Retrieved <span class="nowrap">7 January</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=The+British+Museum&rft.atitle=cameo%3B+jewellery-case&rft_id=https%3A%2F%2Fwww.britishmuseum.org%2Fcollection%2Fobject%2FH_1978-1002-747-a-b&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-71"><span class="mw-cite-backlink"><b><a href="#cite_ref-71">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20110607081210/http://www.mnh.si.edu/earth/text/dynamicearth/6_0_0_GeoGallery/geogallery_specimen.cfm?SpecimenID=4038&categoryID=1&categoryName=Gems&browseType=name">"The Dynamic Earth"</a>. National Museum of Natural History. Archived from <a rel="nofollow" class="external text" href="http://www.mnh.si.edu/earth/text/dynamicearth/6_0_0_GeoGallery/geogallery_specimen.cfm?SpecimenID=4038&categoryID=1&categoryName=Gems&browseType=name">the original</a> on 7 June 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">8 October</span> 2011</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=The+Dynamic+Earth&rft.pub=National+Museum+of+Natural+History&rft_id=http%3A%2F%2Fwww.mnh.si.edu%2Fearth%2Ftext%2Fdynamicearth%2F6_0_0_GeoGallery%2Fgeogallery_specimen.cfm%3FSpecimenID%3D4038%26categoryID%3D1%26categoryName%3DGems%26browseType%3Dname&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-72"><span class="mw-cite-backlink"><b><a href="#cite_ref-72">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGuinness1992" class="citation book cs1">Guinness, Medd (October 1992). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=oqoOYFaIIigC&q=galaxy+opal+"><i>"The Guinness Book of Records 1993</i></a>. Guinness. p. 22. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-85112-978-5" title="Special:BookSources/978-0-85112-978-5"><bdi>978-0-85112-978-5</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160826130908/https://books.google.com/books?id=oqoOYFaIIigC&dq=galaxy+opal&q=galaxy+opal+">Archived</a> from the original on 26 August 2016.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=%22The+Guinness+Book+of+Records+1993&rft.pages=22&rft.pub=Guinness&rft.date=1992-10&rft.isbn=978-0-85112-978-5&rft.aulast=Guinness&rft.aufirst=Medd&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DoqoOYFaIIigC%26q%3Dgalaxy%2Bopal%2B&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-73"><span class="mw-cite-backlink"><b><a href="#cite_ref-73">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation news cs1"><a rel="nofollow" class="external text" href="http://www.abc.net.au/news/2015-08-02/million-dollar-opal-rainbow-virgin-on-display-in-adelaide-museum/6666344?section=sa">"Million-dollar opal Rainbow Virgin to go on display at SA exhibition celebrating centenary"</a>. <i>ABC News</i>. 2 August 2015. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20171217044656/http://www.abc.net.au/news/2015-08-02/million-dollar-opal-rainbow-virgin-on-display-in-adelaide-museum/6666344?section=sa">Archived</a> from the original on 17 December 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">13 January</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=ABC+News&rft.atitle=Million-dollar+opal+Rainbow+Virgin+to+go+on+display+at+SA+exhibition+celebrating+centenary&rft.date=2015-08-02&rft_id=http%3A%2F%2Fwww.abc.net.au%2Fnews%2F2015-08-02%2Fmillion-dollar-opal-rainbow-virgin-on-display-in-adelaide-museum%2F6666344%3Fsection%3Dsa&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-74"><span class="mw-cite-backlink"><b><a href="#cite_ref-74">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.samuseum.sa.gov.au/explore/exhibitions/opals/opals-media-releases">"Opals media releases"</a>. South Australian Museum. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20151229110935/http://www.samuseum.sa.gov.au/explore/exhibitions/opals/opals-media-releases">Archived</a> from the original on 29 December 2015<span class="reference-accessdate">. Retrieved <span class="nowrap">13 January</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Opals+media+releases&rft.pub=South+Australian+Museum&rft_id=http%3A%2F%2Fwww.samuseum.sa.gov.au%2Fexplore%2Fexhibitions%2Fopals%2Fopals-media-releases&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-SAM_media_release_17_May_2017-75"><span class="mw-cite-backlink">^ <a href="#cite_ref-SAM_media_release_17_May_2017_75-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-SAM_media_release_17_May_2017_75-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.samuseum.sa.gov.au/media/53865/4-million-worth-of-the-south-australian-museums-opal-collection-for-display-in-qatar">"$4 million worth of the South Australian Museum's opal collection for display in Qatar"</a>. South Australian Museum. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20171217044656/http://www.samuseum.sa.gov.au/media/53865/4-million-worth-of-the-south-australian-museums-opal-collection-for-display-in-qatar">Archived</a> from the original on 17 December 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">7 July</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=%244+million+worth+of+the+South+Australian+Museum%27s+opal+collection+for+display+in+Qatar&rft.pub=South+Australian+Museum&rft_id=http%3A%2F%2Fwww.samuseum.sa.gov.au%2Fmedia%2F53865%2F4-million-worth-of-the-south-australian-museums-opal-collection-for-display-in-qatar&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-76"><span class="mw-cite-backlink"><b><a href="#cite_ref-76">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.geologypage.com/2016/10/largest-black-opal-world.html">"Largest black opal in the world"</a>. 25 October 2016. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170319114003/http://www.geologypage.com/2016/10/largest-black-opal-world.html">Archived</a> from the original on 19 March 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">18 March</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Largest+black+opal+in+the+world&rft.date=2016-10-25&rft_id=http%3A%2F%2Fwww.geologypage.com%2F2016%2F10%2Flargest-black-opal-world.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> <li id="cite_note-77"><span class="mw-cite-backlink"><b><a href="#cite_ref-77">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.samuseum.sa.gov.au/media/53865/worlds-finest-piece-of-uncut-opal-finds-new-home-at-the-south-australian-museum">"World's finest piece of uncut opal finds new home at the South Australian Museum"</a>. South Australian Museum. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170626033952/https://www.samuseum.sa.gov.au/media/53865/worlds-finest-piece-of-uncut-opal-finds-new-home-at-the-south-australian-museum">Archived</a> from the original on 26 June 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">7 July</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=World%27s+finest+piece+of+uncut+opal+finds+new+home+at+the+South+Australian+Museum&rft.pub=South+Australian+Museum&rft_id=http%3A%2F%2Fwww.samuseum.sa.gov.au%2Fmedia%2F53865%2Fworlds-finest-piece-of-uncut-opal-finds-new-home-at-the-south-australian-museum&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOpal" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Opal&action=edit&section=22" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1235681985">.mw-parser-output .side-box{margin:4px 0;box-sizing:border-box;border:1px solid #aaa;font-size:88%;line-height:1.25em;background-color:var(--background-color-interactive-subtle,#f8f9fa);display:flow-root}.mw-parser-output .side-box-abovebelow,.mw-parser-output .side-box-text{padding:0.25em 0.9em}.mw-parser-output .side-box-image{padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .side-box-imageright{padding:2px 0.9em 2px 0;text-align:center}@media(min-width:500px){.mw-parser-output .side-box-flex{display:flex;align-items:center}.mw-parser-output .side-box-text{flex:1;min-width:0}}@media(min-width:720px){.mw-parser-output .side-box{width:238px}.mw-parser-output .side-box-right{clear:right;float:right;margin-left:1em}.mw-parser-output .side-box-left{margin-right:1em}}</style><style data-mw-deduplicate="TemplateStyles:r1237033735">@media print{body.ns-0 .mw-parser-output .sistersitebox{display:none!important}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}</style><div class="side-box side-box-right plainlinks sistersitebox"><style data-mw-deduplicate="TemplateStyles:r1126788409">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style> <div class="side-box-flex"> <div class="side-box-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png" decoding="async" width="30" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/45px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/59px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span></div> <div class="side-box-text plainlist">Wikimedia Commons has media related to <span style="font-weight: bold; font-style: italic;"><a href="https://commons.wikimedia.org/wiki/Category:Opal" class="extiw" title="commons:Category:Opal">Opal</a></span>.</div></div> </div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1235681985"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1237033735"><div class="side-box side-box-right plainlinks sistersitebox"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1126788409"> <div class="side-box-flex"> <div class="side-box-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/40px-Wiktionary-logo-en-v2.svg.png" decoding="async" width="40" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/60px-Wiktionary-logo-en-v2.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/80px-Wiktionary-logo-en-v2.svg.png 2x" data-file-width="512" data-file-height="512" /></span></span></div> <div class="side-box-text plainlist">Look up <i><b><a href="https://en.wiktionary.org/wiki/opal" class="extiw" title="wiktionary:opal">opal</a></b></i> in Wiktionary, the free dictionary.</div></div> </div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1235681985"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1237033735"><div class="side-box side-box-right plainlinks sistersitebox"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1126788409"> <div class="side-box-flex"> <div class="side-box-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/38px-Wikisource-logo.svg.png" decoding="async" width="38" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/57px-Wikisource-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/76px-Wikisource-logo.svg.png 2x" data-file-width="410" data-file-height="430" /></span></span></div> <div class="side-box-text plainlist"><a href="/wiki/Wikisource" title="Wikisource">Wikisource</a> has original text related to this article: <div style="margin-left: 10px;"><b><a href="https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Opal" class="extiw" title="wikisource:1911 Encyclopædia Britannica/Opal">1911 Encyclopædia Britannica/Opal</a></b></div></div></div> </div> <ul><li><a rel="nofollow" class="external text" href="http://www.farlang.com/gemstones/opal">Farlang opal Hist. References</a> Localities, anecdotes by <a href="/wiki/Theophrastus" title="Theophrastus">Theophrastus</a>, <a href="/wiki/Isaac_Newton" title="Isaac Newton">Isaac Newton</a>, <a href="/wiki/Georg_Agricola" class="mw-redirect" title="Georg Agricola">Georg Agricola</a> etc.</li> <li><a rel="nofollow" class="external text" href="http://gemstone.org/gem-by-gem/english/opal.html">ICA's Opal Page</a>: International Colored Stone Association</li> <li><a rel="nofollow" class="external text" href="http://www.samuseum.sa.gov.au/explore/museum-galleries/opal-fossils">Opal Fossils from the South Australian Museum</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20140213204022/http://www.samuseum.sa.gov.au/explore/museum-galleries/opal-fossils">Archived</a> 13 February 2014 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> Accessed 19 October 2016.</li> <li><a rel="nofollow" class="external text" href="http://webmineral.com/data/Opal.shtml">Opal Mineral data and specimen images</a> Mineralogy Database</li> <li><a rel="nofollow" class="external text" href="https://www.opalworld.com.au/australian-opal-fields/">Opalworld</a> Australian Opal Fields – Map of precious opal deposits</li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist 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.navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Silica_minerals" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Silica_minerals" title="Template:Silica minerals"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Silica_minerals" title="Template talk:Silica minerals"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Silica_minerals" title="Special:EditPage/Template:Silica minerals"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Silica_minerals" style="font-size:114%;margin:0 4em"><a href="/wiki/Silicon_dioxide" title="Silicon dioxide">Silica</a> <a href="/wiki/Mineral" title="Mineral">minerals</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Crystal_structure" title="Crystal structure">Crystalline</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Coesite" title="Coesite">Coesite</a></li> <li><a href="/wiki/Cristobalite" title="Cristobalite">Cristobalite</a></li> <li><a href="/wiki/Keatite" title="Keatite">Keatite</a></li> <li><a href="/wiki/Moganite" title="Moganite">Moganite</a></li> <li><a href="/wiki/Quartz" title="Quartz">Quartz</a></li> <li><a href="/wiki/Seifertite" title="Seifertite">Seifertite</a></li> <li><a href="/wiki/Stishovite" title="Stishovite">Stishovite</a></li> <li><a href="/wiki/Tridymite" title="Tridymite">Tridymite</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Cryptocrystalline" title="Cryptocrystalline">Cryptocrystalline</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Chalcedony" title="Chalcedony">Chalcedony</a></li> <li><a href="/wiki/Chert" title="Chert">Chert</a></li> <li><a href="/wiki/Flint" title="Flint">Flint</a></li> <li><a href="/wiki/Jasper" title="Jasper">Jasper</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Amorphous_solid" title="Amorphous solid">Amorphous</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Fulgurite" title="Fulgurite">Fulgurite</a></li> <li><a href="/wiki/Lechatelierite" title="Lechatelierite">Lechatelierite</a></li> <li><a class="mw-selflink selflink">Opal</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Miscellaneous</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Tiger%27s_eye" title="Tiger's eye">Tiger's eye</a></li> <li><a href="/wiki/Aqeeq" title="Aqeeq">Aqeeq</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Notable varieties</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Chalcedony" title="Chalcedony">Chalcedony</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Agate" title="Agate">Agate</a></li> <li><a href="/wiki/Carnelian" title="Carnelian">Carnelian</a></li> <li><a href="/wiki/Chrome_chalcedony" title="Chrome chalcedony">Chrome chalcedony</a></li> <li><a href="/wiki/Chrysoprase" title="Chrysoprase">Chrysoprase</a></li> <li><a href="/wiki/Heliotrope_(mineral)" title="Heliotrope (mineral)">Heliotrope</a></li> <li><a href="/wiki/Moss_agate" title="Moss agate">Moss agate</a></li> <li><a href="/wiki/Onyx" title="Onyx">Onyx</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a class="mw-selflink selflink">Opal</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Fiorite" title="Fiorite">Fiorite</a></li> <li><a href="/wiki/Geyserite" title="Geyserite">Geyserite</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Quartz" title="Quartz">Quartz</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Amethyst" title="Amethyst">Amethyst</a></li> <li><a href="/wiki/Ametrine" title="Ametrine">Ametrine</a></li> <li><a href="/wiki/Herkimer_diamond" title="Herkimer diamond">Herkimer diamond</a></li> <li><a href="/wiki/Smoky_quartz" title="Smoky quartz">Smoky quartz</a></li> <li><a href="/wiki/Shocked_quartz" title="Shocked quartz">Shocked quartz</a></li> <li><a href="/wiki/Prasiolite" title="Prasiolite">Prasiolite</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div><b><span class="nowrap"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Am%C3%A9thystre_sceptre2.jpg/23px-Am%C3%A9thystre_sceptre2.jpg" decoding="async" width="23" height="28" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Am%C3%A9thystre_sceptre2.jpg/34px-Am%C3%A9thystre_sceptre2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Am%C3%A9thystre_sceptre2.jpg/46px-Am%C3%A9thystre_sceptre2.jpg 2x" data-file-width="2893" data-file-height="3552" /></span></span> </span><a href="/wiki/Portal:Minerals" title="Portal:Minerals">Minerals portal</a></b></div></td></tr></tbody></table><div></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Gemstones" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Gemstones" title="Template:Gemstones"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Gemstones" title="Template talk:Gemstones"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Gemstones" title="Special:EditPage/Template:Gemstones"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Gemstones" style="font-size:114%;margin:0 4em"><a href="/wiki/Gemstone" title="Gemstone">Gemstones</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2"><div>Gemmological classifications by E. Ya. Kievlenko (1980), updated</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Jewellery" title="Jewellery">Jewelry</a> stones</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><i><a href="/wiki/Cardinal_gem" title="Cardinal gem">1st order</a></i></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Diamond" title="Diamond">Diamond</a></li> <li><a href="/wiki/Ruby" title="Ruby">Ruby</a></li> <li><a href="/wiki/Emerald" title="Emerald">Emerald</a></li> <li><a href="/wiki/Sapphire#Blue_sapphire" title="Sapphire">Blue Sapphire</a></li> <li><a href="/wiki/Chrysoberyl#Alexandrite" title="Chrysoberyl">Alexandrite</a></li> <li><a href="/wiki/Pearl#Natural_pearls" title="Pearl">Natural marine pearls</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><i>2nd order</i></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Sapphire#Pink_sapphires" title="Sapphire">Pink sapphire</a></li> <li><a href="/wiki/Demantoid" title="Demantoid">Demantoid</a></li> <li><a href="/wiki/Tsavorite" title="Tsavorite">Tsavorite</a></li> <li><a href="/wiki/Spinel" title="Spinel">Spinel</a></li> <li><a class="mw-selflink-fragment" href="#Precious_opal">Precious Black Opal</a></li> <li><a href="/wiki/Tanzanite" title="Tanzanite">Tanzanite</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><i>3rd order</i></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Sapphire#Sapphires_of_other_colors" title="Sapphire">Yellow, Green, Violet Sapphires</a></li> <li><a href="/wiki/Aquamarine_(gem)" title="Aquamarine (gem)">Aquamarine</a></li> <li>Orange <a href="/wiki/Topaz" title="Topaz">topaz</a> (Imperial)</li> <li><a href="/wiki/Elbaite" title="Elbaite">Elbaite</a></li> <li><a class="mw-selflink-fragment" href="#Other_varieties_of_opal">Precious White and Fire Opal</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><i>4th order</i></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Tourmaline" title="Tourmaline">Tourmaline</a> – Verdelite</li> <li><a href="/wiki/Indicolite" class="mw-redirect" title="Indicolite">Indicolite</a>, polychromous</li> <li><a href="/wiki/Beryl" title="Beryl">Beryl</a> – <a href="/wiki/Heliodor" class="mw-redirect" title="Heliodor">Heliodor</a>, pink, yellow-green</li> <li><a href="/wiki/Topaz" title="Topaz">Topaz</a> yellow, blue, pink</li> <li><a href="/wiki/Peridot" title="Peridot">Peridot</a></li> <li><a href="/wiki/Garnet" title="Garnet">Garnets</a> – <a href="/wiki/Spessartine" title="Spessartine">Spessartine</a> (malaya), <a href="/wiki/Rhodolite" title="Rhodolite">Rhodolite</a>, <a href="/wiki/Almandine" title="Almandine">Almandine</a>, <a href="/wiki/Pyrope" title="Pyrope">Pyrope</a></li> <li><a href="/wiki/Amethyst" title="Amethyst">Amethyst</a></li> <li><a href="/wiki/Citrine_quartz" class="mw-redirect" title="Citrine quartz">Citrine</a></li> <li>Blue <a href="/wiki/Turquoise" title="Turquoise">Turquoise</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Jewelry-Industrial<br />stones</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><i>1st order</i></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Lazurite" title="Lazurite">Lazurite</a></li> <li><a href="/wiki/Jadeite" title="Jadeite">Jadeite</a></li> <li><a href="/wiki/Nephrite" title="Nephrite">Nephrite</a></li> <li><a href="/wiki/Malachite" title="Malachite">Malachite</a></li> <li><a href="/wiki/Amber" title="Amber">Amber</a> (<a href="/wiki/Baltic_amber" title="Baltic amber">Baltic amber</a>)</li> <li><a href="/wiki/Chrysoprase" title="Chrysoprase">Chrysoprase</a></li> <li><a href="/wiki/Charoite" title="Charoite">Charoite</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><i>2nd order</i></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Agate" title="Agate">Agate</a></li> <li><a href="/wiki/Amazonite" title="Amazonite">Amazonite</a></li> <li><a href="/wiki/Rhodonite" title="Rhodonite">Rhodonite</a></li> <li>Colorless, <a href="/wiki/Quartz#Smoky_quartz" title="Quartz">smoky</a> and <a href="/wiki/Quartz#Rose_quartz" title="Quartz">pink</a> <a href="/wiki/Quartz" title="Quartz">quartz</a></li> <li><a href="/wiki/Hematite" title="Hematite">Hematite</a></li> <li>Common <a class="mw-selflink selflink">opal</a></li> <li>Opaque iridescent <a href="/wiki/Feldspar" title="Feldspar">feldspars</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Industrial stones</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Jasper" title="Jasper">Jasper</a></li> <li><a href="/wiki/Graphic_texture" title="Graphic texture">Graphic</a> <a href="/wiki/Granite" title="Granite">granite</a></li> <li><a href="/wiki/Petrified_wood" title="Petrified wood">Petrified wood</a></li> <li><a href="/wiki/Cacholong" title="Cacholong">Cacholong</a> (Porouse <a class="mw-selflink selflink">opal</a>)</li> <li>Marble <a href="/wiki/Onyx" title="Onyx">onyx</a></li> <li><a href="/wiki/Obsidian" title="Obsidian">Obsidian</a></li> <li><a href="/wiki/Listwanite" title="Listwanite">Listwanite</a> (green mica)</li> <li><a href="/wiki/Jet_(lignite)" class="mw-redirect" title="Jet (lignite)">Jet</a></li> <li><a href="/wiki/Selenite_(mineral)" title="Selenite (mineral)">Selenite</a></li> <li><a href="/wiki/Fluorite" title="Fluorite">Fluorite</a></li> <li><a href="/wiki/Serpentinite" title="Serpentinite">Serpentinite</a></li> <li><a href="/wiki/Aventurine" title="Aventurine">Aventurine</a> <a href="/wiki/Quartzite" title="Quartzite">quartzite</a></li> <li><a href="/wiki/Verd_antique" title="Verd antique">Ophicalcite</a> (<a href="/wiki/Serpentinite" title="Serpentinite">Serpentine</a>/<a href="/wiki/Calcite" title="Calcite">Calcite</a>)</li> <li><a href="/wiki/Pagodite" title="Pagodite">Pagodite</a> (<a href="/wiki/Pyrophyllite" title="Pyrophyllite">Pyrophyllite</a>/<a href="/wiki/Talc" title="Talc">Talc</a>)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_individual_gemstones" title="List of individual gemstones">List of individual gemstones</a></li> <li><a href="/wiki/List_of_diamonds" title="List of diamonds">List of diamonds</a></li> <li><a href="/wiki/List_of_emeralds_by_size" title="List of emeralds by size">List of emeralds by size</a></li> <li><a href="/wiki/List_of_sapphires_by_size" title="List of sapphires by size">List of sapphires by size</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div><span class="noviewer" typeof="mw:File"><span title="List-Class article"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/16px-Symbol_list_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/23px-Symbol_list_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/31px-Symbol_list_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/List_of_gemstones_by_species" title="List of gemstones by species">List of gemstones by species</a> <ul><li><b><span class="nowrap"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Am%C3%A9thystre_sceptre2.jpg/23px-Am%C3%A9thystre_sceptre2.jpg" decoding="async" width="23" height="28" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Am%C3%A9thystre_sceptre2.jpg/34px-Am%C3%A9thystre_sceptre2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Am%C3%A9thystre_sceptre2.jpg/46px-Am%C3%A9thystre_sceptre2.jpg 2x" data-file-width="2893" data-file-height="3552" /></span></span> </span><a href="/wiki/Portal:Minerals" title="Portal:Minerals">Minerals portal</a></b></li></ul></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Jewellery" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Jewellery" title="Template:Jewellery"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Jewellery" title="Template talk:Jewellery"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Jewellery" title="Special:EditPage/Template:Jewellery"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Jewellery" style="font-size:114%;margin:0 4em"><a href="/wiki/Jewellery" title="Jewellery">Jewellery</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/List_of_jewellery_types" title="List of jewellery types">Forms</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Anklet" title="Anklet">Anklet</a></li> <li><a href="/wiki/Hair_clip" title="Hair clip">Barrette</a></li> <li><a href="/wiki/Belly_chain" title="Belly chain">Belly chain</a></li> <li><a href="/wiki/Belt_buckle" title="Belt buckle">Belt buckle</a></li> <li><a href="/wiki/Bindi_(decoration)" title="Bindi (decoration)">Bindi</a></li> <li><a href="/wiki/Bolo_tie" title="Bolo tie">Bolo tie</a></li> <li><a href="/wiki/Bracelet" title="Bracelet">Bracelet</a></li> <li><a href="/wiki/Brooch" title="Brooch">Brooch</a></li> <li><a href="/wiki/Chatelaine_(chain)" title="Chatelaine (chain)">Chatelaine</a></li> <li><a href="/wiki/Collar_pin" title="Collar pin">Collar pin</a></li> <li><a href="/wiki/Crown" title="Crown">Crown</a></li> <li><a href="/wiki/Cufflink" title="Cufflink">Cufflink</a></li> <li><a href="/wiki/Earring" title="Earring">Earring</a></li> <li><a href="/wiki/Ferronni%C3%A8re" title="Ferronnière">Ferronnière</a></li> <li><a href="/wiki/Genital_jewellery" class="mw-redirect" title="Genital jewellery">Genital</a></li> <li><a href="/wiki/Lapel_pin" title="Lapel pin">Lapel pin</a></li> <li><a href="/wiki/Necklace" title="Necklace">Necklace</a></li> <li><a href="/wiki/Neck_ring" title="Neck ring">Neck ring</a></li> <li><a href="/wiki/Pectoral_(Ancient_Egypt)" title="Pectoral (Ancient Egypt)">Pectoral</a></li> <li><a href="/wiki/Pendant" title="Pendant">Pendant</a></li> <li><a href="/wiki/Ring_(jewellery)" title="Ring (jewellery)">Ring</a></li> <li><a href="/wiki/Tiara" title="Tiara">Tiara</a></li> <li><a href="/wiki/Tie_chain" title="Tie chain">Tie chain</a></li> <li><a href="/wiki/Tie_clip" title="Tie clip">Tie clip</a></li> <li><a href="/wiki/Tie_pin" title="Tie pin">Tie pin</a></li> <li><a href="/wiki/Toe_ring" title="Toe ring">Toe ring</a></li> <li><a href="/wiki/Watch" title="Watch">Watch</a> <ul><li><a href="/wiki/Pocket_watch" title="Pocket watch">pocket</a></li> <li><a href="/wiki/Watch_strap" title="Watch strap">strap</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Making</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">People</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bench_jeweler" title="Bench jeweler">Bench jeweler</a></li> <li><a href="/wiki/Clockmaker" title="Clockmaker">Clockmaker</a></li> <li><a href="/wiki/Goldsmith" title="Goldsmith">Goldsmith</a></li> <li><a href="/wiki/Jewellery_design" title="Jewellery design">Jewellery designer</a></li> <li><a href="/wiki/Lapidary" title="Lapidary">Lapidarist</a></li> <li><a href="/wiki/Silversmith" title="Silversmith">Silversmith</a></li> <li><a href="/wiki/Watchmaker" title="Watchmaker">Watchmaker</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Processes</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Cameo_(carving)" title="Cameo (carving)">Carving</a></li> <li><a href="/wiki/Metal_casting" title="Metal casting">Casting</a> <ul><li><a href="/wiki/Centrifugal_casting_(silversmithing)" title="Centrifugal casting (silversmithing)">centrifugal</a></li> <li><a href="/wiki/Lost-wax_casting" title="Lost-wax casting">lost-wax</a></li> <li><a href="/wiki/Metal_casting" title="Metal casting">vacuum</a></li></ul></li> <li><a href="/wiki/Vitreous_enamel" title="Vitreous enamel">Enameling</a></li> <li><a href="/wiki/Engraved_gem" title="Engraved gem">Engraving</a></li> <li><a href="/wiki/Filigree" title="Filigree">Filigree</a></li> <li><a href="/wiki/Metal_clay" title="Metal clay">Metal clay</a></li> <li><a href="/wiki/Plating" title="Plating">Plating</a></li> <li><a href="/wiki/Polishing_(metalworking)" title="Polishing (metalworking)">Polishing</a></li> <li><a href="/wiki/Repouss%C3%A9_and_chasing" title="Repoussé and chasing">Repoussé and chasing</a></li> <li><a href="/wiki/Soldering" title="Soldering">Soldering</a></li> <li><a href="/wiki/Stonesetting" title="Stonesetting">Stonesetting</a></li> <li><a href="/wiki/Wire_sculpture" title="Wire sculpture">Wire sculpture</a></li> <li><a href="/wiki/Wire_wrapped_jewelry" title="Wire wrapped jewelry">Wire wrapped jewelry</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Tools</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Draw_plate" title="Draw plate">Draw plate</a></li> <li><a href="/wiki/File_(tool)" title="File (tool)">File</a></li> <li><a href="/wiki/Hammer" title="Hammer">Hammer</a></li> <li><a href="/wiki/Mandrel" title="Mandrel">Mandrel</a></li> <li><a href="/wiki/Pliers" title="Pliers">Pliers</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Materials</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Precious_metal" title="Precious metal">Precious metals</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Gold" title="Gold">Gold</a></li> <li><a href="/wiki/Palladium" title="Palladium">Palladium</a></li> <li><a href="/wiki/Platinum" title="Platinum">Platinum</a></li> <li><a href="/wiki/Rhodium" title="Rhodium">Rhodium</a></li> <li><a href="/wiki/Silver" title="Silver">Silver</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Precious metal <a href="/wiki/Alloy" title="Alloy">alloys</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Britannia_silver" title="Britannia silver">Britannia silver</a></li> <li><a href="/wiki/Colored_gold" title="Colored gold">Colored gold</a></li> <li><a href="/wiki/Crown_gold" title="Crown gold">Crown gold</a></li> <li><a href="/wiki/Electrum" title="Electrum">Electrum</a></li> <li><a href="/wiki/Shakud%C5%8D" title="Shakudō">Shakudō</a></li> <li><a href="/wiki/Shibuichi" title="Shibuichi">Shibuichi</a></li> <li><a href="/wiki/Sterling_silver" title="Sterling silver">Sterling silver</a> <ul><li><a href="/wiki/Argentium_sterling_silver" title="Argentium sterling silver">Argentium</a></li></ul></li> <li><a href="/wiki/Tumbaga" title="Tumbaga">Tumbaga</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Base_metal" title="Base metal">Base metals</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Brass" title="Brass">Brass</a></li> <li><a href="/wiki/Bronze" title="Bronze">Bronze</a></li> <li><a href="/wiki/Copper" title="Copper">Copper</a></li> <li><a href="/wiki/Mokume-gane" title="Mokume-gane">Mokume-gane</a></li> <li><a href="/wiki/Nickel_silver" title="Nickel silver">Nickel silver (alpacca)</a>:</li> <li><a href="/wiki/Niobium" title="Niobium">Niobium</a></li> <li><a href="/wiki/Pewter" title="Pewter">Pewter</a></li> <li><a href="/wiki/Pinchbeck_(alloy)" title="Pinchbeck (alloy)">Pinchbeck</a></li> <li><a href="/wiki/Stainless_steel" title="Stainless steel">Stainless steel</a></li> <li><a href="/wiki/Titanium" title="Titanium">Titanium</a></li> <li><a href="/wiki/Tungsten" title="Tungsten">Tungsten</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Mineral <a href="/wiki/Gemstone" title="Gemstone">gemstones</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Agate" title="Agate">Agate</a></li> <li><a href="/wiki/Amazonite" title="Amazonite">Amazonite</a></li> <li><a href="/wiki/Amethyst" title="Amethyst">Amethyst</a></li> <li><a href="/wiki/Aventurine" title="Aventurine">Aventurine</a></li> <li><a href="/wiki/Beryl" title="Beryl">Beryl</a> (<a href="/wiki/Red_beryl" title="Red beryl">red</a>)</li> <li><a href="/wiki/Carnelian" title="Carnelian">Carnelian</a></li> <li><a href="/wiki/Chrysoberyl" title="Chrysoberyl">Chrysoberyl</a></li> <li><a href="/wiki/Chrysocolla" title="Chrysocolla">Chrysocolla</a></li> <li><a href="/wiki/Diamond" title="Diamond">Diamond</a></li> <li><a href="/wiki/Diopside" title="Diopside">Diopside</a></li> <li><a href="/wiki/Emerald" title="Emerald">Emerald</a></li> <li><a href="/wiki/Fluorite" title="Fluorite">Fluorite</a></li> <li><a href="/wiki/Garnet" title="Garnet">Garnet</a></li> <li><a href="/wiki/Howlite" title="Howlite">Howlite</a></li> <li><a href="/wiki/Jade" title="Jade">Jade</a></li> <li><a href="/wiki/Jasper" title="Jasper">Jasper</a></li> <li><a href="/wiki/Kyanite" title="Kyanite">Kyanite</a></li> <li><a href="/wiki/Labradorite" title="Labradorite">Labradorite</a></li> <li><a href="/wiki/Lapis_lazuli" title="Lapis lazuli">Lapis lazuli</a></li> <li><a href="/wiki/Larimar" title="Larimar">Larimar</a></li> <li><a href="/wiki/Malachite" title="Malachite">Malachite</a></li> <li><a href="/wiki/Marcasite_jewellery" title="Marcasite jewellery">Marcasite</a></li> <li><a href="/wiki/Moonstone_(gemstone)" title="Moonstone (gemstone)">Moonstone</a></li> <li><a href="/wiki/Obsidian" title="Obsidian">Obsidian</a></li> <li><a href="/wiki/Onyx" title="Onyx">Onyx</a></li> <li><a class="mw-selflink selflink">Opal</a></li> <li><a href="/wiki/Peridot" title="Peridot">Peridot</a></li> <li><a href="/wiki/Prasiolite" title="Prasiolite">Prasiolite</a></li> <li><a href="/wiki/Quartz" title="Quartz">Quartz</a> (<a href="/wiki/Smoky_quartz" title="Smoky quartz">smoky</a>)</li> <li><a href="/wiki/Ruby" title="Ruby">Ruby</a></li> <li><a href="/wiki/Sapphire" title="Sapphire">Sapphire</a></li> <li><a href="/wiki/Sodalite" title="Sodalite">Sodalite</a></li> <li><a href="/wiki/Spinel" title="Spinel">Spinel</a></li> <li><a href="/wiki/Sunstone" title="Sunstone">Sunstone</a></li> <li><a href="/wiki/Tanzanite" title="Tanzanite">Tanzanite</a></li> <li><a href="/wiki/Tiger%27s_eye" title="Tiger's eye">Tiger's eye</a></li> <li><a href="/wiki/Topaz" title="Topaz">Topaz</a></li> <li><a href="/wiki/Tourmaline" title="Tourmaline">Tourmaline</a></li> <li><a href="/wiki/Turquoise" title="Turquoise">Turquoise</a></li> <li><a href="/wiki/Variscite" title="Variscite">Variscite</a></li> <li><a href="/wiki/Zircon" title="Zircon">Zircon</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Organic gemstones</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Abalone" title="Abalone">Abalone</a></li> <li><a href="/wiki/Amber" title="Amber">Amber</a></li> <li><a href="/wiki/Ammolite" title="Ammolite">Ammolite</a></li> <li><a href="/wiki/Copal" title="Copal">Copal</a></li> <li><a href="/wiki/Coral" title="Coral">Coral</a> <ul><li><a href="/wiki/Black_coral" title="Black coral">Black</a></li> <li><a href="/wiki/Precious_coral" title="Precious coral">Precious</a></li></ul></li> <li><a href="/wiki/Ivory" title="Ivory">Ivory</a></li> <li><a href="/wiki/Jet_(gemstone)" title="Jet (gemstone)">Jet</a></li> <li><a href="/wiki/Nacre" title="Nacre">Nacre</a></li> <li><a href="/wiki/Operculum_(gastropod)" title="Operculum (gastropod)">Operculum</a></li> <li><a href="/wiki/Pearl" title="Pearl">Pearl</a></li> <li><a href="/wiki/Tortoiseshell" title="Tortoiseshell">Tortoiseshell</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other natural objects</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bezoar" title="Bezoar">Bezoar</a></li> <li><a href="/wiki/Bog-wood" title="Bog-wood">Bog-wood</a></li> <li><a href="/wiki/Ebonite" title="Ebonite">Ebonite (vulcanite)</a></li> <li><a href="/wiki/Gutta-percha" title="Gutta-percha">Gutta-percha</a></li> <li><a href="/wiki/Hair_jewellery" class="mw-redirect" title="Hair jewellery">Hair</a></li> <li><a href="/wiki/Shell_jewelry" title="Shell jewelry">Shell</a> <ul><li><a href="/wiki/Spondylus" title="Spondylus">Spondylus shell</a></li></ul></li> <li><a href="/wiki/Toadstone" title="Toadstone">Toadstone</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Terms</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Art_jewelry" title="Art jewelry">Art jewelry</a></li> <li><a href="/wiki/Carat_(mass)" title="Carat (mass)">Carat</a> (mass)</li> <li><a href="/wiki/Fineness#Carat" title="Fineness">Carat</a> (purity)</li> <li><a href="/wiki/Finding_(jewelcrafting)" title="Finding (jewelcrafting)">Finding</a></li> <li><a href="/wiki/Fineness" title="Fineness">Fineness</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <dl><dt>Related topics</dt> <dd><a href="/wiki/Body_piercing" title="Body piercing">Body piercing</a></dd> <dd><a href="/wiki/Fashion" title="Fashion">Fashion</a></dd> <dd><a href="/wiki/Gemology" title="Gemology">Gemology</a></dd> <dd><a href="/wiki/Metalworking" title="Metalworking">Metalworking</a></dd> <dd><a href="/wiki/Phaleristics" title="Phaleristics">Phaleristics</a></dd> <dd><a href="/wiki/Wearable_art" title="Wearable art">Wearable art</a></dd></dl> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Glass_production_techniques" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Glass_production_techniques" title="Template:Glass production techniques"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Glass_production_techniques" title="Template talk:Glass production techniques"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Glass_production_techniques" title="Special:EditPage/Template:Glass production techniques"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Glass_production_techniques" style="font-size:114%;margin:0 4em"><a href="/wiki/Glass_production" title="Glass production">Glass production</a> techniques</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Commercial<br />techniques</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Float_glass" title="Float glass">Float glass process</a></li> <li><a href="/wiki/Fritted_glass" title="Fritted glass">Fritted glass</a></li> <li><a href="/wiki/Glass_production#Forming_process" title="Glass production">Blowing and pressing (containers)</a></li> <li><a href="/wiki/Glass_(fiber)#Fiber_formation" class="mw-redirect" title="Glass (fiber)">Extrusion / Drawing (glass fibers)</a></li> <li><a href="/wiki/Glass_wool" title="Glass wool">Glass wool</a></li> <li><a href="/wiki/Optical_fiber#Manufacturing" title="Optical fiber">Drawing (optical fibers)</a></li> <li><a href="/wiki/Precision_glass_moulding" title="Precision glass moulding">Precision glass moulding</a></li> <li><a href="/wiki/Overflow_downdraw_method" title="Overflow downdraw method">Overflow downdraw method</a></li> <li><a href="/wiki/Pressed_glass" title="Pressed glass">Pressing</a></li> <li><a href="/wiki/Glass_casting" title="Glass casting">Casting</a></li> <li><a href="/wiki/Flame_polishing" title="Flame polishing">Flame polishing</a></li> <li><a href="/wiki/Etching_(microfabrication)" title="Etching (microfabrication)">Chemical polishing</a></li> <li><a href="/wiki/Diamond_turning" title="Diamond turning">Diamond turning</a></li> <li><a href="/wiki/Rolled_plate_glass" title="Rolled plate glass">Rolling</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Artistic and<br />historic techniques</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/%C4%80ina-k%C4%81ri" title="Āina-kāri">Āina-kāri</a></li> <li><a href="/wiki/Art_glass" title="Art glass">Art glass</a></li> <li><a href="/wiki/Glass_art" title="Glass art">Glass art</a></li> <li><a href="/wiki/Glass_beadmaking" class="mw-redirect" title="Glass beadmaking">Beadmaking</a></li> <li><a href="/wiki/Glassblowing" title="Glassblowing">Blowing</a></li> <li><a href="/wiki/Blown_plate_glass" title="Blown plate glass">Blown plate</a></li> <li><a href="/wiki/Broad_sheet_glass" title="Broad sheet glass">Broad sheet</a></li> <li><a href="/wiki/Caneworking" title="Caneworking">Caneworking</a></li> <li><a href="/wiki/Cased_glass" title="Cased glass">Cased glass</a></li> <li><a href="/wiki/Crown_glass_(window)" title="Crown glass (window)">Crown glass</a></li> <li><a href="/wiki/Cut_glass" title="Cut glass">Cut glass</a></li> <li><a href="/wiki/Cylinder_blown_sheet_glass" title="Cylinder blown sheet glass">Cylinder blown sheet</a></li> <li><a href="/wiki/Engraved_glass" title="Engraved glass">Engraving</a></li> <li><a href="/wiki/Glass_etching" title="Glass etching">Etching</a></li> <li><a href="/wiki/Enamelled_glass" title="Enamelled glass">Enamelled glass</a></li> <li><a href="/wiki/Flashed_glass" title="Flashed glass">Flashed glass</a></li> <li><a href="/wiki/Forest_glass" title="Forest glass">Forest glass</a></li> <li><a href="/wiki/Fourcault_process" title="Fourcault process">Fourcault process</a></li> <li><a href="/wiki/Glass_fusing" title="Glass fusing">Fusing</a></li> <li><a href="/wiki/Glass_mosaic" title="Glass mosaic">Glass mosaic</a></li> <li><a href="/wiki/List_of_glassware" title="List of glassware">Glassware</a></li> <li><a href="/wiki/Lampworking" title="Lampworking">Lampworking</a></li> <li><a href="/wiki/Machine_drawn_cylinder_sheet_glass" title="Machine drawn cylinder sheet glass">Machine drawn cylinder sheet</a></li> <li><a href="/wiki/Millefiori" title="Millefiori">Millefiori</a></li> <li><a href="/wiki/Mirror" title="Mirror">Mirror</a></li> <li><a href="/wiki/Polished_plate_glass" title="Polished plate glass">Polished plate</a></li> <li><a href="/wiki/Porous_glass" title="Porous glass">Porous glass</a></li> <li><a href="/wiki/Rippled_glass" title="Rippled glass">Rippled glass</a></li> <li><a href="/wiki/Satsuma_Kiriko_cut_glass" class="mw-redirect" title="Satsuma Kiriko cut glass">Satsuma Kiriko cut glass</a></li> <li><a href="/wiki/Slumping" title="Slumping">Slumping</a></li> <li><a href="/wiki/Stained_glass" title="Stained glass">Stained glass</a></li> <li><a href="/wiki/Studio_glass" title="Studio glass">Studio glass</a></li> <li><a href="/wiki/Tempered_glass" title="Tempered glass">Tempered glass</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Category:Glass_in_nature" title="Category:Glass in nature">Natural processes</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Glass_with_embedded_metal_and_sulfides" title="Glass with embedded metal and sulfides">Radiative processes</a></li> <li><a class="mw-selflink selflink">Opal formation</a></li> <li><a href="/wiki/Sea_glass" title="Sea glass">Sea glass</a></li> <li><a href="/wiki/Shock_metamorphism" title="Shock metamorphism">Shock metamorphic glass</a>/<a href="/wiki/Impactite" title="Impactite">Impactite</a></li> <li><a href="/wiki/Vitrified_sand" title="Vitrified sand">Vitrified sand</a></li> <li><a href="/wiki/Volcanic_glass" title="Volcanic glass">Volcanic glass</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Glossary_of_glass_art_terms" title="Glossary of glass art terms">Glossary of glass art terms</a></li> <li><a href="/wiki/Glass_recycling" title="Glass recycling">Glass recycling</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"><style data-mw-deduplicate="TemplateStyles:r1038841319">.mw-parser-output .tooltip-dotted{border-bottom:1px dotted;cursor:help}</style></div><div role="navigation" 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