BGS Rock Classification Scheme

Gypsum-wackestone - A type of gypsum-stone, classified on the basis of its depositional texture. In the Rock Classification Scheme, it is a matrix-supported gypsum-stone composed of less than 75% matrix (mud-grade material smaller than 32 µm). British Geological Survey Research Report RR/99/03, section 7.2 and fig. 11.

Code GYWST
Description Gypsum-wackestone - A type of gypsum-stone, classified on the basis of its depositional texture. In the Rock Classification Scheme, it is a matrix-supported gypsum-stone composed of less than 75% matrix (mud-grade material smaller than 32 µm). British Geological Survey Research Report RR/99/03, section 7.2 and fig. 11.
Qualifiers No qualifiers currently exist.
Definition Matrix supported sedimentary rock with components >50% non-carbonate sulphate salts, >50% of non-carbonate salt is gypsum (CaSO4.2H2O). <75% matrix (<0.032mm), composition not defined.
Linked data http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/GYWST

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.