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The Siilinjärvi carbonatite complex, [1] an open-pit mine owned by Yara International, in Siilinjärvi, Finland Coal strip mine in Wyoming. Surface mining, including strip mining, open-pit mining and mountaintop removal mining, is a broad category of mining in which soil and rock overlying the mineral deposit (the overburden) are removed, in contrast to underground mining, in which the ...
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 ...
When coal seams are near the surface, it may be economical to extract the coal using open-cut, also referred to as open-cast, open-pit, mountaintop removal or strip, mining methods. Opencast coal mining recovers a greater proportion of the coal deposit than underground methods, as more of the coal seams in the strata may be exploited.
The units of a stripping ratio can vary between mine types. For example, in coal mining the stripping ratio is commonly referred to as volume/weight. [3], whereas in metal mining, stripping ratio is unitless and is expressed as weight/weight. [2] A stripping ratio can be expressed as a ratio or as a number.
Techniques of surface mining include: open-pit mining, which is the recovery of materials from an open pit in the ground; quarrying, identical to open-pit mining except that it refers to sand, stone and clay; strip mining, which consists of stripping surface layers off to reveal ore underneath; and mountaintop removal, commonly associated with ...
The Mexican Mining Chamber (Camimex) opposes the ban on open-pit mining, saying such a prohibition would cause a 1% contraction in the country's GDP and threaten some 200,000 jobs.
Surface mining, mining conducted down into the ground, but with the sky open above Open-pit mining , where the overburden is removed and put in a different location, leaving a large pit at the end. Strip mining , where the overburden is stripped off and placed onto the area where the mineral (usually coal) has already been mined out, allowing ...
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