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AMERICA... A World Class Gold Producer
The history of United States commercial gold production on a large scale extends back more than 200 years.
Gold was produced in the southern Appalachian region as early as 1792 and perhaps as early as 1775 in southern California. The discovery of gold at Sutter's Mill in California sparked the gold rush of 1849-50, and hundreds of mining camps sprang to life as new deposits were discovered. Gold production increased rapidly. Deposits in the Mother Lode and Grass Valley districts in California and the Comstock Lode in Nevada were discovered during the 1860's, and the Cripple Creek deposits in Colorado began to produce gold in 1892. By 1905 the Tonopah and Goldfield deposits in Nevada and the Alaskan placer deposits had been discovered, and United States gold production for the first time exceeded 4 million troy ounces a year--a level maintained until 1917.
During World War I and for some years thereafter, the annual production declined to about 2 million ounces. When the price of gold was raised from $20.67 to $35 an ounce in 1934, production increased rapidly and again exceeded the 4-million-ounce level in 1937. Shortly after the start of World War II, gold mines were closed by the War Production Board and not permitted to reopen until 1945.
From the end of World War II through 1983, domestic mine production of gold did not exceed 2 million ounces annually. Since 1985, annual production has risen by 1 million to 1.5 million ounces every year. By the end of 1989, the cumulative output from deposits in the United States since 1792 reached 363 million ounces.
Consumption of gold in the United States ranged from about 6 million to more than 7 million troy ounces per year from 1969 to 1973, and from about 4 million to 5 million troy ounces per year from 1974 to 1979, whereas during the 1970's annual gold production from domestic mines ranged from about 1 million to 1.75 million troy ounces. Since 1980, consumption of gold has been nearly constant at between 3 and 3.5 million troy ounces per year. Mine production has increased at a quickening pace since 1980, reaching about 9 million troy ounces per year in 1990, and exceeding consumption since 1986. Prior to 1986, the balance of supply was obtained from secondary (scrap) sources and imports. Total world production of gold is estimated to be about 3.4 billion troy ounces, of which more than two-thirds was mined in the past 50 years. About 45 percent of the world's total gold production has been from the Witwatersrand district in South Africa.
The largest gold mine in the United States is the Homestake mine at Lead, South Dakota. This mine, which is 8,000 feet deep, has accounted for almost 10 percent of total United States gold production since it opened in 1876. It has combined production and reserves of about 40 million troy ounces.
In the past two decades, low-grade disseminated gold deposits have become increasingly important. More than 75 such deposits have been found in the Western States, mostly in Nevada. The first major producer of this type was the Carlin deposit, which was discovered in 1962 and started production in 1965. Since then many more deposits have been discovered in the vicinity of Carlin, and the Carlin area now comprises a major mining district with seven operating open pits producing more than 1,500,000 troy ounces of gold per year.
About 15 percent of the gold produced in the United States has come from mining other metallic ores. Where base metals- -such as copper, lead, and zinc--are deposited, either in veins or as scattered mineral grains, minor amounts of gold are commonly deposited with them. Deposits of this type are mined for the predominant metals, but the gold is also recovered as a byproduct during processing of the ore. Most byproduct gold has come from porphyry deposits, which are so large that even though they contain only a small amount of gold per ton of ore, so much rock is mined that a substantial amount of gold is recovered. The largest single source of byproduct gold in the United States is the porphyry deposit at Bingham Canyon, Utah, which has produced about 18 million troy ounces of gold since 1906.

Because of the discovery and production from the state of Nevada in the 1970s and 1980s, the United States jumped from the world's 6th largest to 2nd largest producer of gold. Nevada's gold now accounts for the majority of the US total. Key to this enormous increase in gold discovery in Nevada were geologic concepts resulting from studies by USGS geologists based in Menlo Park, California. These studies in Nevada, in the late 1950s and 1960s, recognized a unique geologic framework that served as the guide for exploration by nongovernment geologists from many mining companies.
It is the desire and focus of American Goldfields to continue to explore and develop the precious gold resources of America, while constantly increasing shareholder value.
* Graphs based on data issued by Goldsheet and The Gold Institute. Text based partly on content issued by USGS and USGS General Interest Publications
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