BGS Rock Classification Scheme
Microgranite, aplitic
Code | MCGNA |
---|---|
Description | Microgranite, aplitic |
Qualifiers | aplitic |
Definition | Medium-grained, av. between 0.25-2mm normal crystalline intrusive rock with markedly finer grained areas of the same composition; quartz 20-60% of QAPF, feldspar 35-90% alkali feldspar, +/- mica/amphibole |
Linked data | http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/MCGNA |
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.