BGS Rock Classification Scheme
Bituminous-coal - A type of coal. It is a member of the pure humic coal series. The members of the pure humic coal series can be ranked in order as peat (the unlithified form), lignite, bituminous-coal, and anthracite (the lithified forms) based on increasing carbon content and decreasing volatile content. Bituminous-coal is a black, hard and bright coal which typically breaks into rectangular lumps. The bituminous coals can be subdivided in two ways. The first scheme is based on lithotypes which are macroscopically recognisable bands of coal seams. This scheme can be used for describing individual specimens or discrete horizons within a coal seam. Using this scheme, bituminous-coal can be subdivided into vitrain, clarain, fusain, and durain. The second scheme describes the brightness of the coal, and should be used in the field to describe megascopically distinct layers of coal seams. Using this scheme, bituminous-coal can be subdivided into bright-coal, banded-bright-coal, banded-coal, banded-dull-coal, and dull-coal. British Geological Survey Research Report RR/99/03, section 6.1, table 16 and fig. 10.
| Code | BITCOL |
|---|---|
| Description | Bituminous-coal - A type of coal. It is a member of the pure humic coal series. The members of the pure humic coal series can be ranked in order as peat (the unlithified form), lignite, bituminous-coal, and anthracite (the lithified forms) based on increasing carbon content and decreasing volatile content. Bituminous-coal is a black, hard and bright coal which typically breaks into rectangular lumps. The bituminous coals can be subdivided in two ways. The first scheme is based on lithotypes which are macroscopically recognisable bands of coal seams. This scheme can be used for describing individual specimens or discrete horizons within a coal seam. Using this scheme, bituminous-coal can be subdivided into vitrain, clarain, fusain, and durain. The second scheme describes the brightness of the coal, and should be used in the field to describe megascopically distinct layers of coal seams. Using this scheme, bituminous-coal can be subdivided into bright-coal, banded-bright-coal, banded-coal, banded-dull-coal, and dull-coal. British Geological Survey Research Report RR/99/03, section 6.1, table 16 and fig. 10. |
| Qualifiers | No qualifiers currently exist. |
| Definition | Lithified, hard, bright, black mixture of a wide range of plant debris of rarely discernable type. Fine-grained, 0.032-0.25mm organic matrix. 75 to 90% carbon, dry, ash-free. Volatiles 14 to 46%. Largely carbonised, breaks into rectangular lumps. |
| Linked data | http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/BITCOL |
CAVEAT
"Thumbnail" definitions attached to some of the table entries are an interim attempt to provide simple short descriptions of the "unqualified" rock types presented within the BGS Rock Classification Scheme. Every effort has been made to ensure accuracy and consistency but minor contradictions or omissions might be present. The BGS welcomes any feedback pointing out such minor imperfections and/or providing constructive comment and suggestions for improvement of the definitions. In the first instance such feedback should be directed to Dr Tim McCormick.