Bituminous coal

n. soft coal, mineral coal containing hydrocarbons that evaporate easily and tarry substance and burns with a smoky yellow flame

n. bituminous coal, mineral coal containing hydrocarbons that evaporate easily and tarry substance and burns with a smoky yellow flame

Bituminous coal is a relatively hard coal containing a tar-like substance called bitumen. It is of higher quality than lignite coal but of poorer quality than  anthracite coal. Bituminous coal is an organic sedimentary rock formed by diagenetic and submetamorphic compression of peat bog material. Bituminous coal has been compressed and heated so that its primary constituents are the macerals vitrinite, exinite, etc. The carbon content of bituminous coal is around 60-80%; the rest is composed of water, air, hydrogen, and sulfur, which have not been driven off from the macerals.
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Noun
1. rich in tarry hydrocarbons; burns readily with a smoky yellow flame
(synonym) soft coal
(hypernym) coal
(hyponym) cannel coal

A dense, black, soft coal, often with well-defined bands of bright and dull material. The most common coal, with moisture content usually less than 20 percent. Used for generating electricity, making coke, and space heating. See coal.

A shiny black coal that develops from deeply buried lignite through heat and pressure, and that has a carbon content of 80% to 93%, which makes it a more efficient heating fuel than lignite.