Bituminous coal or
black coal is a relatively soft
coal containing a tarlike substance called
bitumen. It is of higher quality than
lignite coal but of poorer quality than
anthracite. Formation is usually the result of high pressure being exerted on lignite. 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.