Copper has the symbol Cu (Latin: cuprum) and atomic number 29. It is a ductile metal with excellent electrical conductivity, and finds extensive use as an electrical conductor, heat conductor, as a building material, and as a component of various alloys. Copper is a reddish-colored metal.
Numerous copper alloys exist, many with important historical and contemporary uses. Speculum metal and bronze are alloys of copper and tin. Brass is an alloy of copper and zinc. Monel metal, also called cupronickel, is an alloy of copper and nickel. While the metal "bronze" usually refers to copper-tin alloys, it also is a generic term for any alloy of copper, such as aluminium bronze, silicon bronze, and manganese bronze.
Copper smelting operations have been traced back to at least 5000 B.C. Copper ranks third in world metal consumption after steel and aluminum.
In 1990 the world copper producton was 9,035,500 metric tons, with Chile as the largest producer - 1,588,400 metric tons.
Any mineral from which copper is extracted, including native
copper, Cu. Currently, the most common source of copper ore is the mineral chalcopyrite
(CuFeS2), which accounts for about 50% of copper production. Others
include chalcocite, Cu2S; bornite, Cu5FeS4;
azurite, Cu3(CO3)2(OH)2;
malachite, Cu2CO3(OH)2; and chrysocolla, CuSiO3.2H2O.
Native copper and the copper sulphides are usually found in veins associated
with igneous intrusions. Chrysocolla and the carbonates are products of the
weathering of copper-bearing rocks. Copper was one of the first metals to be
worked, because it occurred in native form and needed little refining. Today
the main producers are the USA, Russia, Kazakhstan, Georgia, Uzbekistan, Armenia,
Zambia, Chile, Peru, Canada, and the Democratic Republic of Congo (formerly
Zaire).
Porphyry copper deposits are copper orebodies which are associated with porphyritic intrusive rocks. The ore occurs as disseminations along hairline fractures as well as within larger veins, which often form a stockwork. The orebodies typically contain between 0.4 and 1 % copper with smaller amounts of other metals such as molybdenum, silver and gold. They are formed when large quantities of hydrothermal solutions carrying small quantities of metals pass through fractured rock within and around the intrusive and deposit the metals.
A few famous copper mines are:
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