1a. Terms to Know
Coal
A black or brownish sedimentary rock made from organic sediment
Mining
The process of removing coal from the earth
Coal deposit
A deposit of coal in the earth
Underground mining
A type of mining where coal is removed through shafts and tunnels under the earth
Surface mining
A form of mining where the soil and the rock covering the coal deposits are removed
Lignite
A soft coal formed from peat, usually dark brown in color
Sub-bituminous coal
A dull, dark brown to black, soft and crumbly coal. This coal is ranked above lignite in hardness and energy content
Bituminous coal
A black or dark brown coal. This coal is ranked above sub-bituminous and below anthracite in hardness and energy content.
