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Lynch Quarry Site, North Dakota, NRHP-listed and a U.S. National Historic Landmark, a flint quarry that was "a major source of flint found at archaeological sites across North America, and it has been estimated that the material was mined there from 11,000 B.C. to A.D. 1600."
Iron oxide copper gold (IOCG) deposits are considered to be metasomatic expressions of large crustal-scale alteration events driven by intrusive activity. The deposit type was first recognised by discovery and study of the supergiant Olympic Dam copper-gold-uranium deposit (Olympic Dam mine), and South American examples.
The deposit has a mineral resource of 4,1 million tonnes copper at an average copper grade of 0.36% with 5,255 koz of gold and 57 kt of molybdenum as by-products. [ 2 ] The Bozshakol mine and concentrator will have a production life of over 40 years, with estimated annual output of 100 kt of copper cathode equivalent in the first 10 years of ...
Uranium production is carried out in about 13 countries around the world, in 2017 producing a cumulative total of 59,462 tonnes of uranium (tU). The international producers were Kazakhstan (39%), Canada (22%), Australia (10%), Namibia (7.1%), Niger (5.8%), Russian Federation (4.9%), Uzbekistan (4.0%), China (3.2%), United States (1.6%), Ukraine (0.9%), India (0.7%), South Africa (0.5%) and ...
[4] This belief changed when rich mineral deposits (primarily copper and iron) were discovered in the 1840s. The Upper Peninsula's mines produced more mineral wealth than the California Gold Rush , especially after shipping was improved by the opening of the Soo Locks in 1855 and docks in Marquette in 1859.
As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, somewhat brittle, gray metal.
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Annual US mined silver production. Silver mining in the United States began on a major scale with the discovery of the Comstock Lode in Nevada in 1858. The industry suffered greatly from the demonetization of silver in 1873 by the Coinage Act of 1873, known pejoratively as the "Crime of 73", but silver mining continues today.