{"product_id":"obsidian-chihuahua-mexico-1","title":"Obsidian - Chihuahua, Mexico","description":"\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003eA clean, uniformly black obsidian specimen from Chihuahua, Mexico. Obsidian forms when silica-rich (typically rhyolitic) lava is extruded or chilled so rapidly, often at a lava flow margin, dome edge, or where lava meets air or water, that ions have no time to organize into a crystal lattice before the melt locks solid. The result is a true volcanic glass: amorphous at the atomic level, with no internal crystal structure at all, which places it outside the usual mineral classification (minerals require a definite crystalline arrangement). Chemically it's essentially the glassy equivalent of granite or rhyolite, just quenched too fast to crystallize.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003eThe defining physical trait is its conchoidal fracture: obsidian breaks in smooth, curved shell-like surfaces radiating from the point of impact, the same fracture behaviour seen in other glasses and in fine-grained cryptocrystalline materials like chert and flint. This is a solid teaching piece for illustrating amorphous vs. crystalline solids, rapid-cooling igneous textures, and fracture mechanics side by side with true crystalline igneous rock, a natural comparison piece if you're building out a systematic rock\/mineral reference set or classroom kit.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003eThat same conchoidal fracture behaviour is exactly what makes obsidian a longstanding favorite for lapidary work and flintknapping, it takes an extremely sharp edge when struck correctly (obsidian blades can exceed the edge sharpness of surgical steel) and cabs\/polishes to a glossy black finish. If that's your intended use, this piece will work fine for it, but it's being offered here primarily as a geological reference\/display specimen rather than pre-selected knapping material.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003e\u003cspan style=\"color: rgb(255, 42, 0);\"\u003e\u003cstrong\u003e*Please note: Specimens may have sharp edges due to the nature of the material and should be handled carefully to avoid any injury*\u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003e\u003cstrong\u003e\u003cspan style=\"text-decoration: underline;\"\u003eSpecimen Details\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003e\u003cstrong\u003eApprox. specimen weight (g): 982 grams\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003e\u003cstrong\u003eApprox. specimen size (mm): 140mm x 105mm x 55mm\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003e \u003c\/p\u003e","brand":"Rad Man Minerals","offers":[{"title":"Default Title","offer_id":54399984009500,"sku":"3116","price":40.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0726\/5524\/1500\/files\/P9060077.jpg?v=1788725113","url":"https:\/\/radmanminerals.com\/products\/obsidian-chihuahua-mexico-1","provider":"Rad Man Minerals","version":"1.0","type":"link"}