{"product_id":"auction-win-0ead273f-ec51-42f0-84ca-511bff4bf7e5","title":"Auction Win: Copper (arborescent branching) ex. Larry Cull Collection","description":"\u003cp\u003e\u003cstrong\u003eLocality:\u003c\/strong\u003e Keweenaw Peninsula, Michigan, USA\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eSize:\u003c\/strong\u003e Small Cabinet - 6.4 × 4.4 × 1.9 cm\u003c\/p\u003e\n\u003cp\u003eCopper is a native-element mineral composed of Cu, crystallizing in the isometric system with distinctive arborescent branching. Its copper-red surface may tarnish black or green, while dendritic growth produces natural, tree-like forms from branching crystal skeletons. Copper is widely recognized for its essential role in electrical wiring.\u003cbr\u003e\u003cbr\u003eThe Keweenaw Peninsula of Michigan lies along the Midcontinent Rift and is renowned for the world’s largest concentration of native copper hosted chiefly in Precambrian flood basalts and interflow conglomerates. Known as “Copper Country,” it has produced exceptionally pure native copper along with silver, calcite, quartz, prehnite, epidote, chlorite, and zeolites. Commercial mining began in the 1840s and yielded billions of pounds of copper, making the district one of the premier sources of collectible copper specimens. Today, Keweenaw material remains highly prized for its distinctive native-copper forms and the region’s unparalleled geological and mining heritage.\u003c\/p\u003e","brand":"Crystal Castle","offers":[{"title":"Default Title","offer_id":49719891886235,"sku":null,"price":17.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0336\/3012\/6217\/files\/0aa9c50c-c889-4b4c-964c-7b45cc7ac80b.jpg?v=1791148172","url":"https:\/\/www.overtonfamilyjewels.com\/products\/auction-win-0ead273f-ec51-42f0-84ca-511bff4bf7e5","provider":"OFJ's Crystal Castle","version":"1.0","type":"link"}