copper

Copper purification by electrolysis. Pure copper dissolves from the impure copper anode, which decreases in size. The copper is deposited at the cathode, which increases in size. When the purification process is complete the cathode is melted down and cast into bars to be sold to manufacturers, such as producers of electrical wiring.

Red-brown, very malleable and ductile, metallic element, atomic number 29, relative atomic mass 63.546. Its symbol comes from the Latin cuprum. It is one of the transition metals in the periodic table. Copper is used for its durability, pliability, high thermal and electrical conductivity, and resistance to corrosion. It is used in electrical wires and cables, and water pipes and tanks.

Copper was the first metal used systematically for tools by humans; when mined and worked into utensils it formed the technological basis for the Copper Age in prehistory. When alloyed with tin it forms bronze, which is stronger than pure copper and may hold a sharp edge; the systematic production and use of this alloy was the basis for the prehistoric Bronze Age. Brass, another hard copper alloy, includes zinc. The element's name comes from the Latin cyprium (‘Cyprus metal’), due to Cyprus being a major source of copper.

The USA produces about a third of the world's copper output (in 2002, this was 1,140 out of 3,330 tonnes). Other producers are Chile, Canada, Zambia, and the Sheba region of Zaire.

Over 46% of the copper produced is used by the construction trade, followed by 22% for the production of electronic and electrical items.