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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 reducing its depth to about 215 metres (705 ft). Since then it has accumulated about 40 metres (130 ft) of water, leaving 175 metres (574 ft) of the hole visible.
The Big Hole – a former diamond mine in Kimberley, dug to 240 m (790 ft) between 1871 and 1914, making it the deepest hand-excavated pit in the world. Now a museum. The Jagersfontein Mine – operating between 1888 and 1971. This was hand-excavated to 201 m (660 ft) by 1911, and the hand-dug pit was sightly larger than the Big Hole.
The Kola Superdeep Borehole SG-3 (Russian: Кольская сверхглубокая скважина СГ-3, romanized: Kol'skaya sverkhglubokaya skvazhina SG-3) is the deepest human-made hole on Earth (since 1979), which attained maximum true vertical depth of 12,262 metres (40,230 ft; 7.619 mi) in 1989. [1]
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 ...
It is operated by RWE and used for mining lignite. The mine is on the site of the ancient Hambach Forest, which was purchased by RWE in 1978. The company then cut most of the forest down and cleared it to mine. Only 10% of the forest area remains. RWE planned to clear half of the remaining area between 2018 and 2020. This plan was met with ...
Research by historian Steve Lunderstedt in 2005 confirmed that the mine was the biggest hand-excavated hole in the world at 19.65 hectares (48.6 acres), slightly larger than the Big Hole of 17 ha (42 acres) in Kimberley, which had claimed the title up to then. It is probably not the deepest, though, since the final depth of the Big Hole reached ...
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The Hull–Rust–Mahoning Open Pit Iron Mine in Hibbing, Minnesota, United States, is the largest operating open-pit iron mine in Minnesota. The pit stretches more than three miles (5 km) long, two miles (3 km) wide, and 535 feet (163 m) deep. [2]