BGS Rock Classification Scheme
Sapropelic-coal - A type of coal. It is a member of the sapropelic coal series. The members of the sapropelic coal series can be ranked in order as sapropel (the unlithified form), sapropelic-lignite, and sapropelic-coal (the lithified forms) based on increasing carbon content and decreasing volatile content. It is characteristically fine-grained, faintly bedded to homogeneous and massive. It is generally dark in colour with dull to greasy lustre and typically displays conchoidal fracture. Sapropelic coals are subdivided into cannel-coal and boghead-coal based on type of organic matter and other physical properties. British Geological Survey Research Report RR/99/03, section 6.2, table 17 and fig. 10.
| Code | SCOAL |
|---|---|
| Description | Sapropelic-coal - A type of coal. It is a member of the sapropelic coal series. The members of the sapropelic coal series can be ranked in order as sapropel (the unlithified form), sapropelic-lignite, and sapropelic-coal (the lithified forms) based on increasing carbon content and decreasing volatile content. It is characteristically fine-grained, faintly bedded to homogeneous and massive. It is generally dark in colour with dull to greasy lustre and typically displays conchoidal fracture. Sapropelic coals are subdivided into cannel-coal and boghead-coal based on type of organic matter and other physical properties. British Geological Survey Research Report RR/99/03, section 6.2, table 17 and fig. 10. |
| Qualifiers | No qualifiers currently exist. |
| Definition | Sapropelic coal rank. Lithified fine-grained, >75% <0.032mm homogeneous & massive. Dark coloured with dull to greasy lustre & conchoidal fracture. Dry ash free carbon >70%, volatiles <52%. |
| Linked data | http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/SCOAL |
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.