| description | Bituminous coal or black coal is a moderately hard coal containing higher carbon and fewer impurities than lignite coal but of poorer quality than anthracite. Its coloration can be black or sometimes dark brown; often there are well-defined bands of bright and dull material within the seams. These distinctive sequences, which are classified according to either dull, bright-banded or bright, dull-banded, is how bituminous coals are stratigraphically identified. - http://en.wikipedia.org/wiki/Black_coal |