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All you wanted
to know about
> chemistry used in gold mining.
Chemical data on Gold from:
Visit an Australian gold mining and exploration company operating a modern gold mine and developing mineral resources in Thailand:Kingsgate Consolidated Limited - Under the "contact" menu on this website you will find more useful links.
Quantities of gold,
like those of other precious metals, are measured in Troy ounces,
where 1 Troy oz = 1.097 Avoirdupois oz = 31.103 g.
The gold content of gold alloys is expressed in terms of fineness (parts of gold per 1000 parts of total metal) or in carats (parts of gold per 24 parts of total metal).
Most gold is used in jewellery, with lesser quantities for industrial purposes, bar hoarding for investment, and for coin and medallion manufacture. In jewellery and many other uses, gold is usually alloyed with small quantities of other metals to harden it and impart a specific colour.
The largest industrial use of gold is in the electric and electronic industries for plating contacts, terminals, printed circuits and semiconductor systems, but there is a wide range of other uses.
Gold is a common form of international payment and is used by some nations to back their paper currencies. Approximately one third of all the gold mined to date is held by national central banks and other official agencies such as the International Monetary Fund as a support for monetary systems. Large quantities of gold are also held by private banks and institutions for investment and security.
WORLD PRODUCTION & CONSUMPTION
Gold differs from other metals in that the majority of the metal that was ever mined is still in existence. Cumulative world production to date is estimated at about 128,000 t.
South Africa is the world's leading mine producer of gold (522.4 t in 1995). Some 70 other countries produce gold in commercial quantities, including USA (329 t in 1995), Australia (253 t), Canada (150 t), Russia (142 t), China (136 t), Indonesia (74 t), Brazil (67 t), Uzbekistan (64 t), Papua New Guinea (55 t), Ghana (52 t) and Peru (52 t) (GFMS, 1996).
Total world gold supply in 1995 was 3,622 t: 2,272 t from mine production, 201 t from net official sales from national stocks, 602 t from recycling gold scrap, and 548 t from forward sales and option hedging by mining companies (GFMS, 1996).
text excerpted from > NZ Minerals website