Mining of minerals and ore-body:

Mining of minerals and ore-body:

The process or business of extracting ore or minerals from the ground is called mining. It is the selective recovery of minerals and materials from the crust of earth. The term mining industry commonly includes such functions as geological exploration, mineral exploitation by drilling blasting, ore dressing, mineral separation, electrolytic reduction, and smelting and refining.

Mining is broadly divided into three basic methods: opencast and underground. Opencast mining is done on the surface, which involves extraction from a series of successive parallel trenches. Underground mining involves extraction from beneath the surface - from depths as great as some time 10,000 ft (3 km).

The activities of the mining industry begin with geological exploration of economic minerals or ore bodies. Geological exploration is very much complicated, expensive, and highly technical task. After suitable deposits have been found and their worth proved, development, or preparation for mining, is done for exploitation of deposit.

For opencast mining, this involves stripping off overburden, before mineral deposit is approached. Removal of overburden is mostly done by drilling, blasting, lifting the blasted material by excavators on to dumpers and transporting the dumper to a overburden disposal site called overburden dump.

Underground mining include sinking of shafts, driving of adits and other underground openings, and providing for drainage and ventilation before actual mining is done on ore-body. For various development works and for extraction of ore drilling, blasting is necessary. During mining lifting of blasted ore by a machine called load-haul-dump (LHD), transporting them to the surface and filling the void created by exaction by waste material are done.

Associated with mining are many environmental concerns. Large-scale excavation is often necessary to extract a small amount of ore. Ore extraction disrupts the topsoil and can displace local animals and plants, and sometimes native human populations. Runoff can contaminate nearby water sources with pollutants such as the mercury and sodium cyanide used in gold mining. Waste materials and smelters can cause sulfurous dust clouds that result in acid rain. Abandoned strip mines have often been used as unregulated landfills for hazardous wastes.