Coal

Largest Coal Mining companies by Market Cap

1. China Shenhua Energy (
2. Glencore
3. Yankuang Energy (Yanzhou Coal Mining)
4. Coal India
5. Adaro Energy
6. Washington H. Soul Pattinson and Company (WHSP)
7. Yancoal

Coal Mining Methods

The method used to mine coal depends on the terrain and the depth of the coal. Before the early 1970s most coal was taken from underground mines. Since then, coal production has shifted to surface mines.

Underground mining is required when the coal lies more than 200 feet (61 m) below ground. The depth of most underground mines is less than 1,000 feet (305 m), but a few are 2,000 feet (610 m) deep. In underground mines, some coal must be left untouched to form pillars that prevent the mines from caving in.

Three types of underground mines:

1. a shaft mine
2. a slope mine
3. and a drift mine

Surface mines are usually less than 200 feet (61 m) deep and can be developed in flat or hilly terrain.

Coal is a nonrenewable fossil fuel that is combusted and used to generate electricity.

Fossil fuels are formed from the remains of ancient organisms.