{"product_id":"mohs-hardness-classroom-kit","title":"Mohs Hardness Classroom Kit - 8 Specimens","description":"\u003cp\u003eEight real mineral specimens that cover the Mohs hardness scale from 2 to 9, chosen for classroom scratch tests. Students test each one with a fingernail, a copper coin, a steel nail and a glass plate, then put them in order using their own evidence.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e2\u003c\/strong\u003e Selenite (gypsum), round 4\" bowl\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e3\u003c\/strong\u003e Honey calcite, rough chunk 2-4\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e5-5.5\u003c\/strong\u003e Lapis lazuli, rough chunk 2-4\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e6-6.5\u003c\/strong\u003e Labradorite (feldspar), rough chunk 2-4\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e7\u003c\/strong\u003e Clear quartz, small cluster\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e8\u003c\/strong\u003e Spinel crystals in marble (two hardnesses in one rock)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e8.5\u003c\/strong\u003e Alexandrite (chrysoberyl), 1 g bag of tiny crystals\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e9\u003c\/strong\u003e Sapphire (corundum) crystal, 3 to 4.9 g\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eMost school rock kits stop at quartz (7). This set adds spinel, chrysoberyl and sapphire so a class can work the hard end of the scale too. Every piece is natural, so sizes and colours vary.\u003c\/p\u003e","brand":"Stonebridge Imports","offers":[{"title":"Default Title","offer_id":67671072407919,"sku":"BUMOHS8","price":101.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0729\/5130\/0418\/files\/mohs-kit-main.jpg?v=1791224606","url":"https:\/\/stonebridgeimports.com\/products\/mohs-hardness-classroom-kit","provider":"Stonebridge Imports","version":"1.0","type":"link"}