Gold mining in Nevada

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Rawhide, Nevada, 1915
Rawhide, Nevada, 1915

Gold mining in Nevada, a state of the United States, is a major industry, and one of the largest sources of gold in the world. Nevada currently produces 82% of all the gold mined in the United States.[1] Almost all the gold in Nevada comes from large open pit mining and cyanide heap leaching recovery. A number of major mining companies, such as Newmont Mining, operate gold mines in the state. Active gold mines include those at Jerritt canyon.

Although Nevada was known much more for silver in the 1800s, many of the early silver-mining districts also produced considerable quantities of gold. The Comstock Lode, for instance, produced 8.6 million troy ounces (267 tonnes) of gold through 1959, and the Eureka district produced 1.2 million troy ounces (37.3 tonnes).

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[edit] Goldfield

Goldfield was discovered in 1900, and began major gold production in 1902. The ore occurs in altered shear zones in Tertiary dacite and andesite. Total gold production through 1959 was 4.2 million troy ounces (131 tonnes).[2]

[edit] Carlin

Gold was discovered in the vicinity of Carlin in Eureka County in the 1870s, but production was small. Placer deposits were discovered in 1907, but the deposits were too small to cause excitement. It was not until 1961 that the Newmont Mining Corporation found the large low-grade gold deposit at Carlin that the mining industry began to take notice. The Carlin mine began producing gold in 1965, but at the then price of $35 per troy ounce, the ore grade was still too low to cause a rush to northern Nevada. It was not until the gold price shot up in the late 1970s that mining companies rushed to look for similar deposits.[3] The Carlin Trend, part of what is also known as the Carlin Unconformity by geologists, is 5 miles wide and 40 miles long running northwest-southeast, has since produced more gold than the any other mining district in the United States. The trend surpassed 50 million troy ounces (1,555 tonnes) of gold in 2002. The Carlin and other mines along the trend pioneered the method of open-pit mining with cyanide heap leach recovery that is today used at large low-grade gold mines worldwide.

New ore deposits are still being opened along the trend. The South Arturo deposit was discovered by Barrick in 2005. The deposit contains an estimated 1.3 million ounces (40 tonnes) of gold.[4]

[edit] See also

[edit] Cited References

  1. ^ "Mining review," Mining Engineering, May 2007, p.28.
  2. ^ A.H. Koschmann and M.H. Bergendahl, Principal Gold-Producing Districts of the United States, US Geological Survey, Preofessional Paper 610, p.177-178.
  3. ^ Donald M. Hausen and Paul F. Kerr (1969) Fine gold Occurrence at Carlin, Nevada, in Ore Deposits of the United States, 1933-1968, New York: American Institute of Mining Engineers, p.908-940.
  4. ^ Ed Cope and others, "South Arturo: a recent gold discovery on the Carlin Trend," Mining Engineering, Jan. 2008, p.19-25.

[edit] External links