Copper

Copper is a soft transition metal with a pinkish-orange shine when freshly exposed. It carries heat and electricity very well and can be drawn into thin wires, making it important in electrical wiring. On roofs and statues, it slowly develops a green coating of copper compounds called a patina. Copper sometimes occurs naturally as the metal itself, but most is obtained from ores containing copper sulfides, such as chalcopyrite. These ores are mined, crushed and processed to separate the copper-rich minerals. The concentrate is then heated in a smelter to extract the metal, which is purified using an electric current. Copper mixed with tin forms bronze, an alloy used by people for thousands of years.