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Open-pit mining mines mainly include Robussa, Shanka Mountain and Dongqiao. The Dongqiao chromium mine was built in 1967. It was closed in 1983, with a mining depth of 80m and a mining step height of 12m. The mining method is combined with mechanized mining and artificial open pit mining. It uses a wind drill to drill and blast, and uses 0.5m3 to excavate. The rock machine is loaded into the 4t dump truck. The Luobusha chrome ore officially started construction in May 1990. It was completed and put into operation in 1993. According to the mining conditions of the ore body, the design and production stripping ratio is calculated according to 15.3t/t, and the final slope angle of the stope is on the upper and lower sides and the end. The department takes about 45°. The deposit is developed by road, loaded with oil shovel and transported by 8t dump truck. At present, the development of Robussa is limited to the I and II mines, and the part that should be open-pit mining will enter the underground mining stage as production further develops.
The underground mining mines mainly include chrome ore such as Hegen Mountain, Sauron Mountain, Whale and Salto Sea. Among them, the whale chrome ore was completed and put into operation in 1970. In 1982, the pit was closed and the shaft was used for development. The depth of the well was 140m. The main ore body was mainly filled with filling method. The satellite ore body adopts the method of leaving ore and the empty field method. After the blasting, the manhole transportation of the tunnel is carried out. The shaft is mechanized and upgraded. Hegenshan chrome ore began in 1958 small-scale open-pit mining in 1971 designed shafts, depth of 400m, has been the construction 70m, for various reasons after cessation, early 1995, local self-financing be designed new shafts, depth 83.5m, Mining rich ore.
According to statistics, by the end of 1996, a total of 35 deposits (mines) had been mined in different degrees in China. Except for 14 closed pits, 21 mines were being mined. Most of them are small-scale mining by manual or semi-mechanical surface.