In 2007, China overtook South Africa to become the world’s top gold producer. Now China leads the world in gold mining output, having upped its production in 2007 by 12% over 2006, producing 9.7 Moz (276 metric tons) according to GFMS. Production has usually been concentrated in the eastern provinces of Shandong, Henan, Fujian and Liaoning. Recently, western provinces such as Guizhou and Yunnan have seen a sharp increase in their gold output.
Advancements in metallogenic theory and exploration methods for Carlin-type (Nevada) gold deposits by American geologists have been successfully applied to China. Over 100 Carlin-type gold deposit occurrences have been identified in southwest and central China. Chinese Carlin-type deposits are present along the margin of the Precambrian Yangtz craton. Additional deposits lie in the West Qinling area in the Qinling fold belt where many intrusive rocks are present. China has 650 t of gold reserves and plans to increase it to 3,000 t over a 5 years period.
South Africa is now the second largest gold producer. It is the first time since 1905 that the country has not been the largest. About 95% of South Africa's gold mines are underground operations, reaching depths of over 3.8 km. Due to declining ore grades, increased depth of mining, personnel problems, power interruptions and rising production costs the output has been steadily falling.
South Africa has vast gold ore reserves, estimated at 40,000 t and representing about 40% of global reserves. South Africa's main gold producing mines are located on the Archaean Witwatersrand Basin. This basin has been mined for more than 100 years and has produced more than 41,000 t of gold. Unlike most of the world’s major gold deposits, the Witwatersrand ("Wits") is an ancient placer deposit, with gold being hosted by conglomerates and grits. The Wits sedimentary basin stretches through an arc of approximately 400 km across the Free State, North West and Gauteng Provinces.
Gold is produced all over Australia, but Western Australia (WA) is by far the largest gold producing state, producing about 155 t of gold in 2007, which represented just under two-thirds of the country’s total output. New South Wales (NSW) and Queensland are also relatively large producers with NSW producing 35 t in 2007 and Queensland producing 21 t.
Australia's largest producer in 2007 was the Telfer operation in WA where 0.62 Moz was produced. Telfer was followed by the Super Pit at Kalgoorlie where production was almost 0.61 Moz and Sunrise Dam which produced 0.60 Moz (18.7 t). Similar 2008 production figures have been reported by these major gold mines.
In terms of exploration, new gold mineralization was found across Australia and at depths below known deposits in a variety of mineralization styles. The Archaean greenstones of Western Australia's Yilgarn Craton remain a very favorable target but substantial opportunities exist in other provinces too.
Australian Gold Resources Map (PDF) »
Gold production in the United States is mainly concentrated in the states of Nevada, Alaska, Utah, and Colorado. There are also gold operations and exploration projects in Arizona, California, Idaho, Montana, New Mexico, South Dakota, Utah, and Washington.
Nevada is the leading gold-producing state, and ranked fourth after China, South Africa and Australia in gold production worldwide. Mines in Nevada accounted for almost 82% of domestic production in 2006. Almost all the gold in Nevada comes from open pit mining and is recovered by means of cyanide heap leaching. One of the largest gold operations in the U.S. is the Carlin mine in northeast Nevada, which is producing gold from a large low-grade deposit.
In Alaska, gold was produced at lode mines, a dozen large placer mines, and numerous small placer mines, mostly in Alaska and the Western States. Much of the gold produced in Alaska was mined from placer deposits occurring along many of the major rivers and tributaries. The principal placer-mining region has been the Yukon River basin which crosses central Alaska. Beach deposits of the Nome district rank second among productive placer deposits of Alaska.
Gold recovered as a byproduct from the concentrates of Peru’s polymetallic mines amounted to 2.6 t in 2006. Large, medium, and small producers contributed 187 t, while an unknown number of placers exploited by artisan miners reported 15.8 t. Placer gold is being produced mostly in the Inca and the Mariategui Regions and from rivers and streams throughout the jungle. The Inambari River and its tributaries represent a well known placer zone located in southeastern Andes.
The Yanacocha mine in the Andes in northern Peru is considered one of the biggest and most profitable in the world – it has produced over US$7 billion worth of gold to date (2008). The Yanacocha gold deposits are high sulfidation epithermal gold deposits, with varying amounts of silver. The Yanacocha gold district is a 10 km x 4 km zone of altered rocks within a belt of Tertiary volcanics that extends the whole length of Peru. This volcanic arc also hosts the Pierina and Lagunas Norte deposits.
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