BGS Rock Classification Scheme

Felsite, quartz-albite-phyric

Code	FELQAP
Description	Felsite, quartz-albite-phyric
Qualifiers	quartz-albite-phyric
Definition	Generally light coloured fine-grained, aphanitic (>75% crystals <0.25mm) normal crystalline rock; qtz <60% or foids <10% QAPF, remainder dominantly feldspar. Quartz<albite both 5-20% as phenocrysts, larger crystals in finer matrix. Rhyodacite is a felsite
Linked data	http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/FELQAP

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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.