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Introduction to Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile, semi-precious metal with very high thermal and electrical conductivity.
Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish. It is used as a conductor of heat and electricity, a building material, and a constituent of various metal alloys. The metal and its alloys have been used for thousands of years. In the Roman era, copper was principally mined on Cyprus, hence the origin of the name of the metal as сyprium (metal of Cyprus), later shortened to сuprum. Its compounds are commonly encountered as copper salts, which often impart blue or green colors to minerals such as turquoise and have been widely used historically as pigments. Architectural structures built with copper corrode to give green verdigris. Decorative art prominently features copper, both by itself and as part of pigments. Porphyry copper deposits are copper orebodies which are associated with porphyritic intrusive rocks and the fluids that accompany them during the transition and cooling from magma to rock. Circulating surface water or underground fluids may interact with the plutonic fluids. Successive envelopes of hydrothermal alteration typically enclose a core of ore minerals disseminated in often stockwork-forming hairline fractures and veins. Porphyry orebodies typically contain between 0.4 and 1 % copper with smaller amounts of other metals such as molybdenum, silver and gold. Porphyry copper deposits are currently the largest source of copper ore. Most of the known porphyrys are concentrated in: western South and North America and Southeast Asia and Oceana - along the Pacific Ring of Fire; the Caribbean; southern central Europe and the area around eastern Turkey; scattered areas in China, the Mideast, Russia, and the CIS states; and eastern Australia. Only a few are identified in Africa, in Namibia and Zambia; none are known in Antarctica. The greatest concentration of the largest copper porphyrys is in Chile. Almost all mines exploiting large porphyry deposits produce from open pits.
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