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href="https://cs.wikipedia.org/wiki/Konchoid%C3%A1ln%C3%AD_lom" title="Konchoidální lom – Czech" lang="cs" hreflang="cs" data-title="Konchoidální lom" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Karplik_murre" title="Karplik murre – Estonian" lang="et" hreflang="et" data-title="Karplik murre" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Fractura_concoidea" title="Fractura concoidea – Spanish" lang="es" hreflang="es" data-title="Fractura concoidea" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%B4%DA%A9%D8%B3%D8%AA%DA%AF%DB%8C_%D8%B5%D8%AF%D9%81%DB%8C" title="شکستگی صدفی – Persian" lang="fa" hreflang="fa" data-title="شکستگی صدفی" 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/Cassure_concho%C3%AFdale" title="Cassure conchoïdale – French" lang="fr" hreflang="fr" data-title="Cassure conchoïdale" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-io mw-list-item"><a href="https://io.wikipedia.org/wiki/Konkoida_rupturo" title="Konkoida rupturo – Ido" lang="io" hreflang="io" data-title="Konkoida rupturo" data-language-autonym="Ido" data-language-local-name="Ido" class="interlanguage-link-target"><span>Ido</span></a></li><li class="interlanguage-link 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<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">Brittle fracture surface that does not follow any natural planes of separation</div> <style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-More_citations_needed plainlinks metadata ambox ambox-content ambox-Refimprove" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Conchoidal_fracture" title="Special:EditPage/Conchoidal fracture">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br /><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Conchoidal+fracture%22">"Conchoidal fracture"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Conchoidal+fracture%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Conchoidal+fracture%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Conchoidal+fracture%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Conchoidal+fracture%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Conchoidal+fracture%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">December 2009</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p>A <b>conchoidal fracture</b> is a break or <a href="/wiki/Fracture" title="Fracture">fracture</a> of a <a href="/wiki/Brittle" class="mw-redirect" title="Brittle">brittle</a> material that does not follow any natural <a href="/wiki/Cleavage_(crystal)" title="Cleavage (crystal)">planes of separation</a>. <a href="/wiki/Mindat.org" title="Mindat.org">Mindat.org</a> defines <i>conchoidal fracture</i> as follows: "a fracture with smooth, curved surfaces, typically slightly concave, showing concentric undulations resembling the lines of growth of a shell".<sup id="cite_ref-MindatConchoidal_1-0" class="reference"><a href="#cite_note-MindatConchoidal-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> Materials that break in this way include <a href="/wiki/Quartz" title="Quartz">quartz</a>, <a href="/wiki/Chert" title="Chert">chert</a>, <a href="/wiki/Flint" title="Flint">flint</a>, <a href="/wiki/Quartzite" title="Quartzite">quartzite</a>, <a href="/wiki/Jasper" title="Jasper">jasper</a>, and other fine-<a href="/wiki/Crystallite" title="Crystallite">grained</a> or <a href="/wiki/Amorphous_solid" title="Amorphous solid">amorphous</a> materials with a composition of pure <a href="/wiki/Silica" class="mw-redirect" title="Silica">silica</a>, such as <a href="/wiki/Obsidian" title="Obsidian">obsidian</a> and window <a href="/wiki/Glass" title="Glass">glass</a>, as well as a few metals, such as <a href="/wiki/Gallium" title="Gallium">solid gallium</a>. </p><p>Crystalline materials such as quartz also exhibit conchoidal fractures when they lack a <a href="/wiki/Cleavage_(crystal)" title="Cleavage (crystal)">cleavage plane</a> and do not break along a plane parallel to their crystalline faces. So, a <a href="/wiki/Fracture_(mineralogy)" title="Fracture (mineralogy)">conchoidal, or uneven, fracture</a> is not a specific indication of the amorphous character of a mineral, or a material. <a href="/wiki/Amorphous_solid" title="Amorphous solid">Amorphous</a>, <a href="/wiki/Cryptocrystalline" title="Cryptocrystalline">cryptocrystalline</a>, and <a href="/wiki/Crystal" title="Crystal">crystalline</a> materials can all present conchoidal fracture when they lack a preferential cleavage plane. </p><p>Conchoidal fractures can occur in various materials if they are properly <a class="external text" href="https://en.wiktionary.org/wiki/percuss">percussed</a> (struck). Cryptocrystalline silica, such as <a href="/wiki/Chert" title="Chert">chert</a>, or <a href="/wiki/Flint" title="Flint">flint</a>, with this material property were widely sought after, traded, and fashioned into sharp tools in the <a href="/wiki/Stone_Age" title="Stone Age">Stone Age</a>. </p><p>Conchoidal fractures often result in a curved breakage surface that resembles the rippling, gradual curves of a <a href="/wiki/Mussel" title="Mussel">mussel</a> shell; the word "conchoid" is derived from the word for this animal (<a href="/wiki/Ancient_Greek_language" class="mw-redirect" title="Ancient Greek language">Ancient Greek</a>: <span lang="grc">κογχοειδής</span> <i>konchoeidēs</i> < <span title="Ancient Greek (to 1453)-language text"><span lang="grc">κόγχη</span></span> <i>konchē</i>).<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><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> A swelling appears at the point of impact called the <i>bulb of percussion</i>. Shock waves emanating outwards from this point leave their mark on the stone as ripples. Other conchoidal features include small <a href="https://en.wiktionary.org/wiki/fissure" class="extiw" title="wikt:fissure">fissures</a> emanating from the bulb of percussion. </p><p>They are defined in contrast to the <a href="/wiki/Facet" title="Facet">faceted</a> fractures often seen in single <a href="/wiki/Crystal" title="Crystal">crystals</a> such as semiconductor <a href="/wiki/Wafer_(electronics)" title="Wafer (electronics)">wafers</a> and <a href="/wiki/Gemstone" title="Gemstone">gemstones</a> and to the high-energy <a href="/wiki/Ductile" class="mw-redirect" title="Ductile">ductile</a> fracture surfaces desirable in most structural applications.<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. (November 2013)">citation needed</span></a></i>]</sup> </p> <ul class="gallery mw-gallery-traditional"> <li class="gallerybox" style="width: 235px"> <div class="thumb" style="width: 230px; height: 190px;"><span typeof="mw:File"><a href="/wiki/File:Lipari-Obsidienne_(5).jpg" class="mw-file-description" title="Obsidian gives conchoidal fractures."><img alt="Obsidian gives conchoidal fractures." src="//upload.wikimedia.org/wikipedia/commons/thumb/1/17/Lipari-Obsidienne_%285%29.jpg/200px-Lipari-Obsidienne_%285%29.jpg" decoding="async" width="200" height="150" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/17/Lipari-Obsidienne_%285%29.jpg/300px-Lipari-Obsidienne_%285%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/17/Lipari-Obsidienne_%285%29.jpg/400px-Lipari-Obsidienne_%285%29.jpg 2x" data-file-width="3648" data-file-height="2736" /></a></span></div> <div class="gallerytext"><a href="/wiki/Obsidian" title="Obsidian">Obsidian</a> gives conchoidal fractures.</div> </li> <li class="gallerybox" style="width: 235px"> <div class="thumb" style="width: 230px; height: 190px;"><span typeof="mw:File"><a href="/wiki/File:2017-Obsidian-conchoidal-fracture.jpg" class="mw-file-description" title="Conchoidal fracture in obsidian"><img alt="Conchoidal fracture in obsidian" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/bd/2017-Obsidian-conchoidal-fracture.jpg/198px-2017-Obsidian-conchoidal-fracture.jpg" decoding="async" width="198" height="160" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/bd/2017-Obsidian-conchoidal-fracture.jpg/297px-2017-Obsidian-conchoidal-fracture.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/bd/2017-Obsidian-conchoidal-fracture.jpg/396px-2017-Obsidian-conchoidal-fracture.jpg 2x" data-file-width="1383" data-file-height="1117" /></a></span></div> <div class="gallerytext">Conchoidal fracture in <a href="/wiki/Obsidian" title="Obsidian">obsidian</a></div> </li> <li class="gallerybox" style="width: 235px"> <div class="thumb" style="width: 230px; height: 190px;"><span typeof="mw:File"><a href="/wiki/File:Flintasten.JPG" class="mw-file-description" title="Conchoidal fracture in flint"><img alt="Conchoidal fracture in flint" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/48/Flintasten.JPG/200px-Flintasten.JPG" decoding="async" width="200" height="150" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/48/Flintasten.JPG/300px-Flintasten.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/48/Flintasten.JPG/400px-Flintasten.JPG 2x" data-file-width="2288" data-file-height="1712" /></a></span></div> <div class="gallerytext">Conchoidal fracture in <a href="/wiki/Flint" title="Flint">flint</a></div> </li> <li class="gallerybox" style="width: 235px"> <div class="thumb" style="width: 230px; height: 190px;"><span typeof="mw:File"><a href="/wiki/File:Conch_fract_glass.jpg" class="mw-file-description" title="Multiple conchoidal fractures in knapped glass"><img alt="Multiple conchoidal fractures in knapped glass" src="//upload.wikimedia.org/wikipedia/commons/thumb/7/7a/Conch_fract_glass.jpg/200px-Conch_fract_glass.jpg" decoding="async" width="200" height="150" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/7a/Conch_fract_glass.jpg/300px-Conch_fract_glass.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7a/Conch_fract_glass.jpg/400px-Conch_fract_glass.jpg 2x" data-file-width="1417" data-file-height="1063" /></a></span></div> <div class="gallerytext">Multiple conchoidal fractures in <a href="/wiki/Knapping" title="Knapping">knapped</a> <a href="/wiki/Glass" title="Glass">glass</a></div> </li> </ul> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Subsets">Subsets</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Conchoidal_fracture&action=edit&section=1" title="Edit section: Subsets"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Several subdefinitions exist, for instance on the Webmineral website:<sup id="cite_ref-WebminderalFracture_4-0" class="reference"><a href="#cite_note-WebminderalFracture-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p> <ul><li>Brittle—conchoidal: very brittle fracture producing small, conchoidal fragments</li> <li>Brittle—subconchoidal: brittle fracture with subconchoidal fragments</li> <li>Conchoidal—irregular: irregular fracture producing small, conchoidal fragments</li> <li>Conchoidal—uneven: uneven fracture producing small, conchoidal fragments</li> <li>Subconchoidal: fractures developed in brittle materials characterized by semi-curving surfaces</li></ul> <div class="mw-heading mw-heading2"><h2 id="Lithics">Lithics</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Conchoidal_fracture&action=edit&section=2" title="Edit section: Lithics"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In <a href="/wiki/Lithic_flake" title="Lithic flake">lithic</a> <a href="/wiki/Stone_tool" title="Stone tool">stone tools</a>, conchoidal fractures form the basis of flint <a href="/wiki/Knapping" title="Knapping">knapping</a>, since the shape of the broken surface is controlled only by the <a href="/wiki/Stress_(physics)" class="mw-redirect" title="Stress (physics)">stresses</a> applied, and not by some preferred orientation of the material. This property also makes such fractures useful in engineering, since they provide a permanent record of the stress state at the time of <a href="/wiki/Failure" title="Failure">failure</a>. As conchoidal fractures can be produced only by mechanical impact, rather than <a href="/wiki/Frost" title="Frost">frost</a> cracking for example, they can be a useful method of differentiating <a href="/wiki/Stone_Age" title="Stone Age">prehistoric</a> stone tools from natural stones. </p> <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=Conchoidal_fracture&action=edit&section=3" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239009302">.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"><a href="/wiki/File:WikiProject_Geology.svg" class="mw-file-description"><img alt="icon" src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e7/WikiProject_Geology.svg/28px-WikiProject_Geology.svg.png" decoding="async" width="28" height="28" class="mw-file-element" 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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"><ol class="references"> <li id="cite_note-MindatConchoidal-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-MindatConchoidal_1-0">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://www.mindat.org/glossary/conchoidal_fracture">Conchoidal fracture</a> at <a href="/wiki/Mindat.org" title="Mindat.org">Mindat.org</a></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</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 class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.merriam-webster.com/dictionary/conchoidal">"Conchoidal"</a>. <i>Merriam-Webster Online</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2010-10-30</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Merriam-Webster+Online&rft.atitle=Conchoidal&rft_id=https%3A%2F%2Fwww.merriam-webster.com%2Fdictionary%2Fconchoidal&rfr_id=info%3Asid%2Fen.wikipedia.org%3AConchoidal+fracture" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.04.0057:entry=kogxoeidh/s"><span title="Ancient Greek (to 1453)-language text"><span lang="grc">κογχοειδής</span></span></a>, <a rel="nofollow" class="external text" href="https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.04.0057:entry=ko/gxh"><span title="Ancient Greek (to 1453)-language text"><span lang="grc">κόγχη</span></span></a>. <a href="/wiki/Henry_Liddell" title="Henry Liddell">Liddell, Henry George</a>; <a href="/wiki/Robert_Scott_(philologist)" title="Robert Scott (philologist)">Scott, Robert</a>; <i><a href="/wiki/A_Greek%E2%80%93English_Lexicon" title="A Greek–English Lexicon">A Greek–English Lexicon</a></i> at the <a href="/wiki/Perseus_Project" class="mw-redirect" title="Perseus Project">Perseus Project</a>.</span> </li> <li id="cite_note-WebminderalFracture-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-WebminderalFracture_4-0">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://webmineral.com/help/Fracture.shtml">Mineral Tenacity and Fracture</a> at Webmineral</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=Conchoidal_fracture&action=edit&section=5" 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:Conchoidal_fracture" class="extiw" title="commons:Category:Conchoidal fracture">Conchoidal fracture</a></span>.</div></div> </div> <ul><li><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Wiktionary-logo-en-v2.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/16px-Wiktionary-logo-en-v2.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/24px-Wiktionary-logo-en-v2.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/32px-Wiktionary-logo-en-v2.svg.png 2x" data-file-width="512" data-file-height="512" /></a></span> The dictionary definition of <a href="https://en.wiktionary.org/wiki/conchoid" class="extiw" title="wiktionary:conchoid"><i>conchoid</i></a> at Wiktionary</li></ul>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; 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