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The world's largest quarries are located on all the world's continents. Their formation is the result of long-term surface mining. It is one of the simplest and cheapest ways to extract limestone, diamonds, iron ore, coal and other minerals from the surface layers of the earth's crust. Quarries are created artificially and exist only as long as humans maintain them. Extraction of minerals in quarries without building shafts is common on all continents of the planet. The principle of surface mining consists in the fact that the thicker layers of waste rock, which are located above the ore, are divided into horizontal layers inside the mine field, the so-called overburden, which is mined from top to bottom, with the upper layers coming in turn before the lower ones. #Pandora TV#