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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]
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 ...
Sican tumi, or ceremonial knife, Peru, 850–1500 CE. Metallurgy in pre-Columbian America is the extraction, purification and alloying of metals and metal crafting by Indigenous peoples of the Americas prior to European contact in the late 15th century.
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]
The earliest gold artifacts were discovered at the site of Wadi Qana in the Levant. [13] Silver is estimated to have been discovered in Asia Minor shortly after copper and gold. [14] There is evidence that iron was known from before 5000 BC. [15] The oldest known iron objects used by humans are some beads of meteoric iron, made in Egypt in ...
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]
Copper mining also produces gold and silver as byproducts. [2] Byproduct molybdenum from copper mining makes Arizona the nation's second-largest producer of that metal. Although copper mineralization was found by the earliest Spanish explorers of Arizona, the territory was remote, and copper could seldom be profitably mined and shipped.
Iron oxide copper-gold deposits are also often associated with other valuable trace elements such as uranium, bismuth and rare-earth metals, although these accessories are typically subordinate to copper and gold in economic terms. Some examples include the Olympic Dam, South Australia, and Candelaria, Chile deposits.