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Mining is a very diverse field with different aspects to it. Just like there are many ways to prepare foods, so too there are many different ways that minerals are extracted from the earth.

Here are the various ways in which mining can occur: The main two divisions
of mining are Surface mining and Underground mining.

Surface Mining

Surface mines are mining operations that delve into rock toextract deposits of mineral resources that are close to the surface. In most forms of surface mining, heavy equipment, such as earthmovers, first removes the overburden (the soil and rock above the deposit). Next, huge machines such as drag line excavators extract the mineral.

Once the material has been removed, the land is recovered for safe use on the surface through a process called reclamation.

There are several variations of surface mining...

Placer Mining

Placer mining involves any type of mining where raw minerals are deposited in sand or gravel or on the surface and are picked up without having to drive, use dynamite or any other significant means. This is an older form of mining.The simplest technique of placer gold mining is panning. In panning, some sediment is placed in a large metal pan, combined with a generous amount of water, and agitated so that the sand flows over the side. Any gold particles contained in the sand, due to the higher density of gold, will tend to remain on the bottom of the pan after all of the sand and mud have been removed. The same principle may be employed on a larger scale by constructing a short sluice box, with barriers along the bottom to slow the movement of gold particles. This method better suits excavation with shovels or similar implements to feed sediment into the device.

Strip Mining

Strip mining is the practice of mining a seam of mineral ore by first removing all of the soil and rock that lies on top of it (the overburden). It is similar to open-pit mining in many regards.

Strip mining is only practical when the ore body to be excavated is relatively near the surface. Since colossal quantities of material often need to be removed, the excavating machinery used in strip mining is often among the largest such equipment ever constructed; drag line excavators and bucket-wheel excavators are common examples. There are two forms of strip mining - area strip mining, which is used on fairly flat terrain, to extract deposits over a large area. Contour strip mining, usually used in hilly terrain, involves cutting terraces in mountainsides following the contour of the land.

Mountaintop removal

Mountaintop removal (MTR) is a relatively new form of coal mining that involves the mass restructuring of earth in order to reach sediment as deep as 1,000 feet below the surface. Mountaintop removal requires that the targeted land be first clear-cut and then leveled by explosives.

Hydraulic

Hydraulic mining involves high pressure water. The water is sprayed at an area of rock and/or gravel and the water breaks the rock up, dislodging ore and placer deposits. The water/oremixture is then milled. This is a very destructive way to mine and has been outlawed in most areas.

Open Pit

Open pit mines involve digging large open holes in the ground as opposed to a small shaft in hard rock mining. This method of mining is most often used with minerals like copper and molybdenum. Open pit mines are very large are mostly away from urban areas.. Mining operations of this scale were not done too often in the 19th century.

Dredging

Dredging is a method often used to bring up underwater mineral deposits. Although dredging is usually employed to clear or enlarge waterways for boats, it can also recover significant amounts of underwater minerals relatively efficiently and cheaply.

Underground Mining

Underground mining refers to a group of techniques used for the extraction of valuable minerals or other geological materials from the earth. In contrast to the other main type of excavation, surface mining, sub-surface mining requires equipment and people to operate under the surface of the earth.

There are several variations of underground mining:

Drift mining

Drift mining is a method of accessing valuable geological material, such as coal, by cutting into the side of the earth, rather than tunneling straight downwards. Drift mines have horizontal entries into the coal seam from a hillside. Drift mines are distinct from slope mines, which have an inclined entrance from the surface to the coal seam. If possible, though, drifts are driven at just a slight incline so that removal of material can be assisted by gravity.

Slope mining

Slope mining is a method of accessing valuable geological material, such as coal. A sloping access shaft travels downwards towards the coal seam. Slope mines differ from shaft and drift mines, which access resources by tunneling straight down or horizontally, respectively.

Shaft mining

Shaft mining is a type of underground mining done by use of a mine shaft. A mine shaft is a vertical passageway used for access to an underground mine. On the surface above the shaft stands a building known as the head frame, which in previous years contained a winding engine and in modern times contains an electric hoist controller. This raises and lowers the cage within the shaft. The cage serves as a lift for the transportation of minerals, equipment, and workers.

Hard Rock

Hard Rock mining refers to various techniques used to mine ore bodies by creating underground "rooms" supported by surrounding pillars of standing rock. Terms for this include stope and pillar, room and pillar, long hole stoping, benching, vertical crater retreat, block caving, sub level caving

Hard rock mining is used for mining many ore types such as gold, copper, zinc and diamonds. There are a number of mining methods that are used to extract the mineral bearing rock from the host rock. Typically some means of support is required in order to maintain that openings that are made by mining. This can be done by pillars which are then mined following the backfilling of the initial stopes.

Coarse ore is mucked out using gravity to help move it down rock raises or shafts to waiting trains of ore cars used to move it to the surface. These trains can travel through long drifts or tunnels ending in portals to the mills on the surface. Ore is also moved in skip buckets hauled up shafts and emptied into bins beneath surface head frame towers for transport to the mill. Ore is also hauled in large trucks up declines to the surface.

Borehole Mining

Borehole Mining (BHM) is a remote operated method of mining of mineral resources through boreholes by means of high pressure water jets. This process can be carried-out from land surface, open pit floor, underground mine or floating platform or vessel through pre-drilled boreholes.