{"product_id":"geological-survey-of-michigan-the-upper-peninsula-copper-bearing-rocks-1873-map-p-8-006539","title":"Geological Survey of Michigan—The Upper Peninsula—Copper bearing rocks 1873 map","description":"\u003cp align=\"left\"\u003e'Geological Survey of Michigan—Map of the Upper Peninsula'\u003c\/p\u003e\u003cp align=\"left\"\u003e\u003cbr\u003e\u003c\/p\u003e\u003cp align=\"left\"\u003e\u003cem\u003eA large and important 19th-century geological map of Michigan’s Upper Peninsula, issued by the Geological Survey of Michigan in 1873, at the height of iron and copper exploitation in the Lake Superior region. Finely hand-coloured to show geological formations, the map is accompanied by a detailed legend identifying copper-bearing rocks, iron-bearing formations, and associated stratigraphy, reflecting its practical purpose as mining intelligence rather than purely academic geology. It covers the key mining districts of the Upper Peninsula, including the Keweenaw Peninsula, Marquette, and Menominee ranges, with coastlines, rivers, and settlements clearly delineated. Produced during the formative period of large-scale copper and iron mining, the map represents an authoritative early synthesis of the region’s mineral geology and is particularly sought after by collectors of American mining history, Lake Superior copper, and 19th-century geological surveys.\u003c\/em\u003e\u003c\/p\u003e","brand":"Antiquemapsandprints.com","offers":[{"title":"Default Title","offer_id":52367310618971,"sku":"P-8-006539","price":280.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0923\/9583\/1643\/files\/P-8-006539a_e46eaf45-8b97-43c4-b402-433c6edf47a7.jpg?v=1770910923","url":"https:\/\/www.antiquemapsandprints.com\/fr\/products\/geological-survey-of-michigan-the-upper-peninsula-copper-bearing-rocks-1873-map-p-8-006539","provider":"Antiquemapsandprints.com","version":"1.0","type":"link"}