| 词条 | Gold mining in Nevada |
| 释义 |
}} 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. In 2017 Nevada produced {{convert|5641538|ozt|kg|-1}} of gold worth $7.052 billion, representing 71% of gold produced in the United States and 5.6% of the world's production.[1][2] Total gold production recorded from Nevada from 1835 to 2017 totals {{convert|200350000|ozt|t}}, worth over US$260.5 billion at 2019 values.[3][4] Much of Nevada's gold production comes from large open pit mining using heap leaching recovery. The Nevada mining industry supported an average 14,387 direct employees in 2017, with about 75,000 additional jobs related to providing goods and services needed by the mining industry. The average pay for mining industry employees during this time was $95,121 per year, second highest of all employment sectors in Nevada.[2] Major mining companies such as Newmont Mining and Barrick Gold Corporation operate many of the state's gold mines. Active mines include those at Jerritt Canyon and the Carlin Trend. Although Nevada was known much more for silver in the 19th century, many of the early silver mining districts also produced considerable quantities of gold. The Comstock Lode produced {{convert|8600000|ozt|t}} of gold through 1959, and the Eureka district produced {{convert|1200000|ozt|t}}. The Robinson copper mine has produced well over {{convert|2700000|ozt|t}} gold, along with over 4 billion pounds (1,500,000 tonnes) of copper. Carlin TrendGold 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 much 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 price then 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.[6] The Carlin Trend, part of what is also known as the Carlin Unconformity, is {{convert|5|mi|km|sigfig=1}} wide and {{convert|40|mi|km|sigfig=1}} long running northwest-southeast, has since produced more gold than any other mining district in the United States. The trend surpassed {{convert|50000000|ozt|t}} 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 discovered and developed along the trend. The South Arturo deposit was discovered by Barrick Gold in 2005. The deposit contains an estimated {{convert|1300000|ozt|t}} of gold.[7] GoldfieldGoldfield was discovered in 1902, and began major gold production in 1904. The ore occurs in altered shear zones in Tertiary dacite and andesite. Total gold production through 1959 was {{convert|4200000|ozt|t}}.[8]Robinson/ElyThe Robinson district at Ely, Nevada produced about {{convert|3000000|ozt|t}} of gold through 1990, as a byproduct of copper mining.[9] In 2017 the Robinson Mine produced 112,633,428 pounds of copper, 37,897 troy ounces of gold and 652,763 pounds of molybdenite with 617 employees.[2] Gold royaltiesAll mineral and gold production on public and private lands in Nevada is subject to a Net Royalty payable to the State. The gross proceeds from the sale of minerals minus allowable deductions determine the taxable net proceeds. If the net proceeds from sales by a mine in the taxable year total $4 million or more, the tax rate is 5%. For less profitable mines the tax rate is graduated down to 2%. Miners' net proceeds are also subject to federal corporate income tax of 21%.[10][11] Because the NPM tax is an ad valorem property tax, the amount of the net proceeds times the property tax rate goes to the county where the mineral was extracted. Any additional amount of tax paid up to the 5% goes to the State.[10] In 2017-2018 the Nevada net proceeds royalty raised $155.1 million (down from $255.6 million in 2012) from gold and silver production, of which the counties received $87.5 million (down from $127 million in 2012).[11] Gold Mining Companies in Nevada
See also
References1. ^{{cite web|title=Mineral Commodity Summaries 2018 |url=https://minerals.usgs.gov/minerals/pubs/mcs/2018/mcs2018.pdf|publisher=U.S. Geological Survey|last1= George|first1=Micheal W.|location=Reston, Virginia|pages=70-71|format=pdf|date=31 January 2018|accessdate=22 March 2019}} 2. ^1 2 {{cite web| last1=Perry |first1=Rick |last2=Visher|first2=Mike |title=Major Mines of Nevada 2017 |url=http://minerals.nv.gov/uploadedFiles/mineralsnvgov/content/Programs/Mining/MiningForms/mm2017_Major_Mines_all.pdf |website=Nevada Division of Minerals|publisher=Nevada Bureau of Mines and Geology|accessdate=22 March 2019|format=pdf|date=2018}} 3. ^{{cite web |title=Major Mines of Nevada |url=https://pubs.nbmg.unr.edu/Pamphlets-s/1862.htm |website=NBMG Publications |publisher=Nevada Bureau of Mines and Geology |accessdate=27 March 2019}} 4. ^{{cite web |last1=Coyner |first1=Alan R. |title=Update on Nevada Mineral Production and Exploration |url=http://minerals.nv.gov/uploadedFiles/mineralsnvgov/content/Programs/Mining/MiningForms/Prod-Explor-Activity_2013_Presentation_NWMA.pdf |website=State of Nevada Division of Minerals |publisher=Northwest Mining Association |accessdate=27 March 2019 |location=Reno, NV |format=ppt |date=4 December 2014}} 5. ^Western Region Gold Deposits at USGS 6. ^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. 7. ^Ed Cope and others, "South Arturo: a recent gold discovery on the Carlin Trend," Mining Engineering, Jan. 2008, p.19-25. 8. ^A.H. Koschmann and M.H. Bergendahl, Principal Gold-Producing Districts of the United States, US Geological Survey, Professional Paper 610, p.177-178. 9. ^Laurence P. James, 1990, "Gold in the Ely (Robinson) copper district, White Pine County, Nevada," in Gold in Porphyry Copper Systems, US Geological Survey, Bulletin 1857-E, p.E28. 10. ^1 {{cite book|title=Understanding Nevada’s Net Proceeds of Minerals Tax|date=2008|publisher=Nevada Taxpayers Association |location= Carson City, NV|url=http://www.nevadataxpayers.org/pdf/minerals-tax-2007-08.pdf}} 11. ^1 {{cite web|title=2017-2018 Net Proceeds of Minerals Bulletin |url=https://tax.nv.gov/LocalGovt/PolicyPub/ArchiveFiles/NetProceedsBulletins/2017-18_Net_Proceeds_Bulletin_-_Final. |website=Nevada Department of Taxation|publisher=Division of Local Government Services|accessdate=22 March 2019|location=Carson City, NV|format=pdf|date=15 June 2018}} External links
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