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This list of deepest mines includes operational and non-operational mines that are at least 2,212 m (7,257 ft), which is the depth of Veryovkina Cave, the deepest known natural cave in the world. The depth measurements in this list represent the difference in elevation from the entrance of the mine to the deepest excavated point.
Coal mining. Coal mining is the process of extracting coal from the ground or from a mine. Coal is valued for its energy content and since the 1880s has been widely used to generate electricity. Steel and cement industries use coal as a fuel for extraction of iron from iron ore and for cement production.
Deep sea mining is the extraction of minerals from the seabed of the deep sea. The main ores of commercial interest are polymetallic nodules, which are found at depths of 4–6 km (2.5–3.7 mi) primarily on the abyssal plain. The Clarion-Clipperton Zone (CCZ) alone contains over 21 billion metric tons of these nodules, with minerals such as ...
Mponeng is an ultra-deep tabular gold mine in South Africa in the Witwatersrand Basin of the Gauteng Province. [1] Previously known as Western Deep Levels No1 Shaft, the mine began operations in 1986. [2] It is one of the most substantial gold mines in the world in terms of production and magnitude, reaching over 4 kilometres (2.5 mi) below the ...
Mining. Mining of sulfur from a deposit at the edge of Ijen 's crater lake, Indonesia. Mining is the extraction of valuable geological materials and minerals from the surface of the Earth. Mining is required to obtain most materials that cannot be grown through agricultural processes, or feasibly created artificially in a laboratory or factory.
From mid-July 1871 [3] to 1914 up to 50,000 miners dug the hole with picks and shovels, [4] yielding 2,720 kilograms (6,000 lb; 13,600,000 carats) of diamonds. The Big Hole has a surface of 17 hectares (42 acres) and is 463 metres (1,519 ft) wide. It was excavated to a depth of 240 metres (790 ft), but then partially infilled with debris ...
Before 1800 a great deal of coal was left in place because extraction was still primitive. As a result, in the deep Tyneside pits (300 to 1,000 ft deep), only about 40 percent of the coal could be extracted. The use of wooden pit props to support the roof was an innovation first introduced about 1800.
A 3D diagram of a modern underground mine with shaft access. Underground hard-rock mining refers to various underground mining techniques used to excavate "hard" minerals, usually those containing metals, [1] such as ore containing gold, silver, iron, copper, zinc, nickel, tin, and lead. It also involves the same techniques used to excavate ...