Gold mining in the United States
Gold mining in the United States has taken abode back the analysis of gold at the Reed acreage in North Carolina in 1799.
US gold assembly abundantly added during the 1980s, due to aerial gold prices and the use of abundance leaching to balance gold from broadcast low-grade deposits in Nevada and added states.
In 2007 the United States produced about 240 tonnes of gold, authoritative it the fourth-largest gold-producing nation, abaft Australia, South Africa, and China.[1] Most gold produced today in the US comes from ample open-pit abundance bleed mines in the accompaniment of Nevada. The US is a net exporter of gold.[2]
Gold mining by state
Alabama
Gold was apparent in Alabama about 1830, anon afterward the Georgia Gold Rush. The arch districts were the Arbacoochee commune in Cleburne County, mostly from placer deposits, and the Hog Mountain commune in Tallapoosa County, which produced 24 thousand troy ounces (750 kg) from veins in schist. [3]orter of gold.[2]
Alaska
Russian campaign apparent placer gold in the Kenai River in 1848, but no gold was produced. Gold mining started in 1870 from placers southeast of Juneau.[4] Today, best gold assembly in Alaska is from the Fort Knox mine, a ample accessible pit and cyanide leaching operation in the Fairbanks mining district. The Fort Knox abundance produced 333 thousand troy ounces (10.3 tonnes) of gold in 2006. Alaska produced a absolute of 40.3 actor troy ounces of gold from 1880 through the end of 2007.
Arizona
Arizona has produced added than 16 actor troy ounces (498 tonnes) of gold.
Gold mining in Arizona reportedly began in 1774 back Spanish priest Manuel Lopez directed Papago Indians to ablution gold from alluvium on the flanks of the Quijotoa Mountains, Pima County. Gold mining contiued there until 1849, back the Mexican miners were absorbed abroad by the California Gold Rush. Other gold mining beneath Spanish and Mexican aphorism took abode in the Oro Blanco commune of Santa Cruz County, and the Arivaca distrct, Pima County.[5]
Mountain man Pauline Weaver apparent placer gold on the east ancillary of the Colorado River in 1862. Weaver's analysis started a gold blitz to the now apparition boondocks of La Paz, Arizona.
The gold-bearing quartz veins of the Vulture Mine, southwest of Wickenburg, in Maricopa County were apparent in 1863. The abundance produced 366 thousand ounces of gold through 1959.[6]
The San Francisco district, which includes the towns of Oatman and Katherine in Mohave County was apparent in 1863 or 1864, but saw little action until a blitz to the commune occurred in 1902. The commune produced 2.0 actor ounces of gold through 1959.[7]
The aftermost gold abundance to accomplish in Arizona was the Gold Road abundance at Oatman, which shut bottomward in 1998. Patriot Gold is analysis conduct at the Moss abundance at Oatman.[8]Columbus Gold is currently accomplishing analysis conduct for gold at four affairs in western Arizona.
In 2006, all of Arizona's gold assembly came as a byproduct of chestnut mining.
California
Spanish prospectors apparent gold in the Potholes commune amid 1775 and 1780, forth the Colorado River, in present Imperial County, California, about ten afar northeast from Yuma, Arizona. The gold was recovered from dry placers. Other placer deposits on the west coffer of the Colorado River were bound discovered, including the Picacho and Cargo Muchacho districts.
Placer gold deposits were apparent at San Ysidro in San Diego County in 1828, San Francisquito Canyon and Placerita Canyon in Los Angeles County in 1835 and 1842, respectivelyduction came as a byproduct of chestnut mining.
Major gold mining in California started in 1848 during the California Gold Rush. Gold assembly in California ailing in 1852, at 3.9 actor troy ounces (121 tonnes) produced in that year. But the placer deposits formed in the aboriginal years were bound exhausted, and assembly crashed. Hardrock mining (in California alleged quartz mining) began in 1849, and placer mining by hydraulic mining began in 1852. Despite the fresh mining methods, by 1865 assembly was 867 thousand troy ounces (27 tonnes), beneath than one-quarter of aiguille production.
Production sank to 412 thousand troy ounces (12.8 tonnes) in 1929, but again soared to added than 1.4 actor troy ounces (43.5 tonnes) for anniversary year 1939 through 1941, afterwards the amount was aloft from $20.67 to $35 per ounce. However, the federal government, in War Assembly Board Order L-208, ordered gold mines closed, to chargeless up assets for the war accomplishment during World War II, and assembly fell to 148 thousand troy ounces (4.6 tonnes) in 1943. Post-war gold assembly never accomplished the aiguille of the aboriginal 1940s, as aggrandizement and the anchored amount of gold breakable its value.[9]
The better gold-mining commune in California is the acclaimed Mother Lode of the Sierra Nevada. Apparent in the aboriginal 1850s, the lode is a area one to four afar advanced and alive 120 afar northwest-southeast from El Dorado County in the north, through Amador, Calaveras, and Tuolumne counties, to Mariposa County in the south. The gold of the Mother Lode is in quartz veins aural phyllite, schist, slate, and greenstone. Through 1959, the Mother Lode produced about 13.3 actor troy ounces (414 tonnes) of gold.[10]
The second-largest gold-mining commune in California was Grass Valley-Nevada City commune in Nevada County. Gold in Holocene gravels was apparent in 1850, followed a few years after by hydraulic mining of Tertiary gravels. By 1880, best of the mining had confused to lode deposits, such as the Empire Mine. Through 1959, the commune produced 10.4 actor troy ounces (323 tonnes) of lode gold, and 2.2 actor troy ounces (68.4 tonnes) of placer gold.[11]
The affluent placer deposits of the Columbia Basin-Jamestown-Sonora commune were apparent in 1853. Almost all the gold was begin at the abject of Quaternary gravels, but some alluvion mines were formed in Tertiary gravels. Total assembly was about 5.9 actor troy ounces (183 tonnes) of gold.[12]
In 2007, California produced 9,400 ounces (1603 kg) of gold from two mines. The Mesquite abundance in Imperial County restarted alive mining in 2007, accepting been abeyant back 2001. The alone added gold ambassador in the state, the Briggs abundance in Inyo County chock-full mining in 2004, but continues to aftermath baby amounts of gold from the bleed pads, from ahead mined ore.[13]
Emgold Mining is activity through the allowing action to reopen the Idaho Maryland gold abundance at Grass Valley, Nevada County.
Colorado
Gold was apparent in 1858 during the Pike's Peak Gold Rush in the around of abreast Denver in 1858, but the deposits were small. The aboriginal important gold discoveries in Colorado were in the Central City-Idaho Springs commune in January 1859. Three Colorado mines abide to aftermath gold. The Cripple Creek & Victor abundance at Victor, an open-pit abundance bleed operation endemic by AngloGold Ashanti, is the arch producer, with 283 thousand troy ounces (8.8 tonnes) of gold in 2006. Other alive gold mines in the accompaniment are underground Golden Wonder abundance abreast Lake City, and the Cash and Rex mines in the Gold Hill mining commune in Boulder County, Colorado.[14]
Georgia
Georgia is accustomed with a absolute actual assembly of 871 thousand ounces of gold from 1830 through 1959.[15] Although a historically important gold producer, the accompaniment does not anon aftermath any gold .
Idaho
Gold was aboriginal apparent in Idaho in 1860, at Pierce.
The arch actual gold-producing commune is the Boise Basin in Boise County, which was apparent in 1862 and produced 2.9 actor troy ounces (90.2 tonnes), mostly from placers.[16]
The French Creek-Florence commune in Idaho County began in the 1860s, and has produced about 1 actor troy ounces (31 tonnes) from placers.
The Argent City commune in Owyhee County began bearing in 1863, and fabricated over 1 actor troy ounces (31 tonnes), mostly from lode deposits.
The Coeur d’Alene commune in Shoshone County has fabricated 440 thousand troy ounces (13.7 tonnes) of gold as byproduct to argent mining.[17]
In 2006, alive gold mines in Idaho included the Argent Strand abundance and the Bond mine.[18]
Maryland
Gold was appear in Maryland as aboriginal as 1830, but no assembly resulted. Placer gold was apparent at Great Falls abreast Washington, DC in 1861 during the American Civil War by Union soldiers from California. After the war a cardinal of mines were opened on gold-bearing quartz veins in Montgomery County. No gold assembly has been appear back 1951. Total assembly was about 6 thousand troy ounces (190 kg).[19]
Michigan
Approximately 29 thousand troy ounces (900 kg) of gold were produced from the Ropes gold abundance northeast of Ishpeming in Marquette County, Michigan. The underground mine, originally operated from 1880 to 1897, and reopened from 1975-1989, extracted gold from quartz veins in peridotite.[20]
Montana
Gold was aboriginal apparent in Montana in 1852, but mining did not activate until 1862, back gold placers were apparent at Bannack, Montana in 1862. The consistent gold blitz resulted in added placer discoveries, including those at Virginia City in 1863, and at Helena and Butte in 1864.[21] In 1867, the Atlantic Cable Quartz Lode was located.
The Butte district, although mined primarily for copper, produced 2.9 actor ounces (91 tonnes) of gold through 1990, about all as a byproduct of chestnut production.[22]
Current alive asperous gold mines accommodate the Montana Tunnels mine, and the Golden Sunlight mine. Alive gold placers accommodate the Browns Gulch placer and the Confederate Gulch placer. Gold is additionally produced from three platinum mines in the Stillwater ablaze complex: the Stillwater mine, the Lodestar mine, and the East Boulder Project.[23]
Nevada
New Mexico
Nevada is now the arch gold-producing accompaniment in the nation, in 2007 bearing 80% of the gold mined in the United States.[2] About all the gold in Nevada comes from ample accessible pit mining and cyanide abundance leaching recovery. A cardinal of above mining companies, such as Newmont Mining, accomplish gold mines in the state. Active gold mines accommodate Jerritt Canyon and the Getchell Mine.Gold was aboriginal apparent in New Mexico in 1828 in the “Old Placers” commune in the Ortiz Mountains, Santa Fe County, New Mexico. The placer gold analysis was followed by analysis of a adjacent lode deposit.[24]
In 2007 all gold assembly in New Mexico (13 thousand troy ounces) came as a byproduct of chestnut mining from two ample accessible pit mines in Grant County. However, two primary gold mines are actuality readied for production: the Northstar abundance in Rio Arriba County, and the San Lorenzo Claims abundance in Socorro County.[25]
North Carolina
North Carolina was the armpit of the aboriginal gold blitz in the United States, afterward the analysis of a 17 batter (7.7 kg) gold asset by 12-year old Conrad Reed in a brook at his father’s acreage in 1799. The Reed Gold Mine, south of Georgeville in Cabarrus County, North Carolina produced about 50 thousand troy ounces (1.6 tonnes) of gold from lode and placer deposits.[26]
Gold was produced from 15 districts, about all in the Piedmont arena of the state. Total gold assembly is estimated at 1.2 actor troy ounces (37.3 tonnes).
Oregon
Although gold mines are advance over abundant of Oregon, about all of the gold produced has appear from two arch areas: the Klamath Mountains in southwest Oregon, including Coos, Curry, Douglas, Jackson and Josephine counties; and the Blue Mountains in northeast Oregon, mostly in Baker and Grant counties.
Prospectors from Illinois apparent placer gold in the Klamath Mountains of southwest Oregon in 1850, starting a blitz to the area. Lode gold deposits were additionally discovered.
Travellers forth the Oregon Trail apprenticed for the Willamette Valley are said to accept apparent gold in northeastern Oregon in 1845, but no assembly resulted. Mining in ardent did not activate until 1861.[27]
Pennsylvania
About 37 thousand troy ounces (1.2 tonnes) of gold was produced from the Cornwall adamant abundance bristles afar south of Lebanon, Lebanon County, Pennsylvania. Although the drop produced adamant back 1742, no gold was appear from the abundance until 1908.[28]
South Carolina
South Carolina had a cardinal of lode gold mines forth the Carolina Slate Belt.[29]
The Haile drop was apparent in Lancaster County in 1827, and at atomic 275 thousand ounces of gold were extracted intermittently amid again and 1942, back the gold abundance was ordered bankrupt as nonessential to the war effort. Beginning in 1951, the drop was mined for associated sericite, which was acclimated as a white filler.[30] Gold is associated with silicic, kaolinitic, and pyritic about-face of greenschist-grade felsic metavolcanics.[31] The abundance was reopened as an accessible pit in the 1980s, and operated until 1992. Kinross Gold Corporation's affirmation of the Haile armpit was nominated for a US Bureau of Acreage Management "Hardrock Mineral Environmental Award."
The Brewer abundance operated from 1828 to 1995, and is now a federal Superfund site.[32]
Kennecott Minerals operated the Ridgeway open-pit gold abundance from 1988 to 1999, and the acreage is now actuality reclaimed by Kennecott.
The Barite Hill abundance operated from 1990 to 1994.
South Dakota
The alone operating gold abundance in South Dakota is the Wharf mine, an accessible pit abundance bleed operation.[33]
Tennessee
Placer gold was apparent on Coker Creek in Monroe County, Tennessee in 1827. The commune produced about 9 thousand troy ounces (300 kg).[34]
Texas
Some affairs accept been biconcave for gold on the Llano Uplift of axial Texas. Gold affairs accommodate the Heath abundance and the Babyhead district, both in Llano County, and the Axial Texas abundance in Gillespie County. Gold production, if any, is not known.[35]
Utah
Most gold produced in Utah today is a byproduct of the huge Bingham Canyon chestnut mine, southwest of Salt Lake City. In 2006, the Bingham Canyon abundance produced 16.3 tonnes of gold, authoritative it the fourth-largest gold ambassador in the US.[36] Over its life, Bingham Canyon has produced added than 23 actor ounces (715 tonnes) of gold.
The Barneys Canyon abundance in Salt Lake County, the aftermost primary gold abundance to accomplish in Utah, chock-full mining in 2001, but is still convalescent gold from its abundance leaching pads. Utah gold assembly was 460 thousand troy ounces (14 tonnes) in 2006.[37]
Virginia
Washington
Gold was aboriginal apparent in Washington in 1853, as placer deposits in the Yakima Valley. Assembly from the accompaniment never exceeded 50,000 troy ounces per year until the mid-1930s, back ample adamantine bedrock deposits were developed, the Chelan Lake and Wenatchee deposits in Chelan County, and the Republic drop in Ferry County. Assembly through 1965 is estimated to be 2.3 actor ounces.[38]
Wyoming
Gold was apparent at the South Pass-Atlantic City-Sweetwater commune in present Fremont County in 1842. The placers were formed intermittently until 1867, back the aboriginal important gold attitude was discovered, and prospectors and miners rushed to the area.. The towns of South Pass City, Atlantic City, and Miner's Delight catered to the miners. The commune was about bare by 1875, and was formed alone intermittently afterward. Total gold assembly was about 300 thousand troy ounces (9.3 tonnes). In 1962, the commune became the armpit of a above adamant mine.[39]
Gold was aboriginal apparent in Washington in 1853, as placer deposits in the Yakima Valley. Assembly from the accompaniment never exceeded 50,000 troy ounces per year until the mid-1930s, back ample adamantine bedrock deposits were developed, the Chelan Lake and Wenatchee deposits in Chelan County, and the Republic drop in Ferry County. Assembly through 1965 is estimated to be 2.3 actor ounces.[38]
Gold was apparent at the South Pass-Atlantic City-Sweetwater commune in present Fremont County in 1842. The placers were formed intermittently until 1867, back the aboriginal important gold attitude was discovered, and prospectors and miners rushed to the area.. The towns of South Pass City, Atlantic City, and Miner's Delight catered to the miners. The commune was about bare by 1875, and was formed alone intermittently afterward. Total gold assembly was about 300 thousand troy ounces (9.3 tonnes). In 1962, the commune became the armpit of a above adamant mine.[39]
Controversy
Many US gold mines are amid on accessible land, but the mining companies pay no royalties to the US government. Gold mines accomplish beneath the General Mining Act of 1872, (enacted beneath the President Ulysses S Grant administration), a law that permits them to pay no royalties. Fighting reforms to accept the gold mining industry pay royalties, the bounded association agency in Elks County, Nevada says that royalties would force mining companies to cut jobs and move elsewhere. [40]
