Bingham Canyon

The Bingham Canyon Mine is an open-pit mine extracting a large porphyry copper deposit southwest of Salt Lake City, Utah, USA, in the Oquirrh Mountains. It is owned by Rio Tinto plc through Kennecott Utah Copper Corporation which operates the mine, a concentrator and a smelter. The mine has been in production since 1906, and has resulted in the creation of a pit over 0.75 mile (1.2 km) deep, 2.5 miles (4 km) wide, and covering 1,900 acres (7.7 km²). According to Kennecott, it is the world's largest man-made excavation.
Over its life, Bingham Canyon has proven to be one of the world's most productive mines. As of 2004, ore from the mine has yielded more than 17 million tons (15.4 Mt) of copper, 23 million ounces (715 t) of gold, 190 million ounces (5,900 t) of silver, and 850 million pounds (386 kt) of molybdenum. The value of these resources is greater than the Comstock Lode, Klondike, and California gold rush mining regions combined. Cumulatively, Bingham Canyon has produced more copper than any other mine in the world, although mines in Chile, Arizona, and New Mexico now exceed Bingham Canyon's annual production rate. High molybdenum prices in 2005 made the molybdenum produced at Bingham Canyon in that year worth even more than the copper. The value of the metal produced in 2006 at Bingham Canyon was US$1.8 billion dollars. The mine is regarded as one of the most up-to-date integrated copper operations in the world, employing 1,400 people. The smelting and refining facilities are recognised as being among the world's best for environmental protection practice and achievement. (...) more....