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Open-pit mining, also known as open-cast or open-cut mining and in larger contexts mega-mining, [1] is a surface mining technique that extracts rock or minerals from the earth. Open-pit mines are used when deposits of commercially useful ore or rocks are found near the surface where the overburden is relatively thin. In contrast, deeper mineral ...
The open-pit style of mining superseded underground operations because it was far more economical and much less dangerous than underground mining. Within the first year of operation, the pit extracted 17,000 tons of ore per day at a grade of 0.75% copper. Ultimately, about 1,000,000,000 tons of material were mined from the Berkeley Pit.
The Chino open-pit copper mine in New Mexico Chalcopyrite specimen from Huarón mine, Peru. Copper extraction refers to the methods used to obtain copper from its ores.The conversion of copper ores consists of a series of physical, chemical, and electrochemical processes.
The mine is the largest human-made excavation, and deepest open-pit mine in the world, [4] [5] which is considered to have produced more copper than any other mine in history – more than 19,000,000 short tons (17,000,000 long tons; 17,000,000 t). [5]
Morenci mine open pit in 2012. The red rocks in the upper benches, and the outcrops in the background, are in the leached capping. It appears that the bottom of the pit is in the mixed oxide-sulfide zone, and that is also what the two haul trucks in the foreground are carrying. Click to enlarge photo. Bingham Canyon mine in 2005. The gray rocks ...
ASARCO (American Smelting and Refining Company) is a mining, smelting, and refining company based in Tucson, Arizona, which mines and processes primarily copper. The company has been a subsidiary of Grupo México since 1999. Its three largest open-pit mines are the Mission, Silver Bell and Ray mines in Arizona. Its mines produce 350,000,000 to ...
The mine was started as the Chino Copper Company in 1909 by mining engineer John M. Sully and Spencer Penrose, [1] [2] [3] and is currently owned and operated by Freeport-McMoRan Inc. subsidiaries. The area where the mine is located is at an average elevation of 5,699 feet (1,737 m).
The Bethlehem concentrator continued to operate on ore from the Valley Copper deposit until June 1989. Production on the Valley Copper mine, now the largest mine and most noticeable feature, began in January 1983. [5] For fifty years the ore was dug using shovels and open pit methods. A very large pit ensued--half a mile deep and two miles in ...