What Are The Methods Of Mining?

As minerals occur in so many different ways, and are found in different depths of the earth's crust, different methods are employed to extract them:

Open-cast mining, this is easiest and the cheapest way of mining minerals that occur near the earth's surface. It involves the removal of the overburden lying above the mineral-breaking rock strata and extracting the ores using mechanical shovels and excavators. The ores are then loaded onto trucks to be carried away for processing as in many iron ore mines. The open-cast method is also quarrying for rocks, limestone and marble.

Underground mining; when area lies deep in the earth's crust, as in most deep–seated coal seems and underground mining is employed. Vertical shafts are sunk into the ground to reach mineral seams, Underground tunnels for galleries, supported by timber pit-props or concrete beams to hold up the roofs, are laid to extract the ores. Underground trucks carry the ores to the foot of the shaft for hoisting to the surface. Underground mining is more difficult, more risky and more expensive method of mining.

Alluvial mining; when minerals occur in alluvial deposits such as alluvial tin in Malaysia, the placer or alluvial mining method is used. This is a way of recovering rather than mining the mineral. The cheaper gravel pump and the more expensive dredge are used to recover minerals ores from the alluvial deposits.