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Copper deposits in Wisconsin and Upper Peninsula of Michigan in the Mid-continental Rift System. Copper was discovered one mile northeast of Mineral Point in Iowa County of southwest Wisconsin in 1837 or 1838. The deposit was mined until 1842, then intermittently through 1875, producing an estimated 680 tonnes of copper. [72]
Native copper nugget from glacial drift, Ontonagon County, Michigan. An example of the raw material worked by the people of the Old Copper Complex. The Old Copper complex or Old Copper culture is an archaeological culture from the Archaic period of North America's Great Lakes region. Artifacts from some of these sites have been dated from 6500 ...
Copper bells, axe heads and ornaments from various parts of Chiapas (1200–1500) on display at the Regional Museum in Tuxtla Gutierrez, Chiapas.. The emergence of metallurgy in pre-Columbian Mesoamerica occurred relatively late in the region's history, with distinctive works of metal apparent in West Mexico by roughly 800 CE, and perhaps as early as 600 CE. [1]
In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600. [12] Copper metallurgy was flourishing in South America, particularly in Peru around 1000 AD; it proceeded at a much slower rate on other ...
This means that many, though they could make metal objects and weapons, continued to use their flint tools, which could maintain a sharper edge for much longer. The unalloyed copper could simply not compete, and in the later days of the Old Copper Culture the metal was almost exclusively used for ceremonial items. [45]
In South America a copper mask dated to 1000 BC found in the Argentinian Andes is the oldest known copper artifact discovered in the Andes. [111] Peru has been considered the origin for early copper metallurgy in pre-Columbian America , but the copper mask from Argentina suggests that the Cajón del Maipo of the southern Andes was another ...
Gold-copper ore, concentrated and leached 16 (2018) [6] 16 Lisbon Valley San Juan County, Utah: Lisbon Valley Mining Company Copper ore, open pit, heap leached 10–15 (2018) [9] 17 Miami: Gila County, Arizona: Freeport-McMoRan: Copper ore, leached 5 (2021) [2] 18 Carlota Gila County, Arizona: KGHM Polska Miedź: Porphyry copper open pit ...
Porphyry copper deposits represent an important resource and the dominant source of copper that is mined today to satisfy global demand. [6] Via compilation of geological data, it has been found that the majority of porphyry deposits are Phanerozoic in age and were emplaced at depths of approximately 1 to 6 kilometres with vertical thicknesses on average of 2 kilometres. [6]