Rhyolite Hand Sample
Rhyolite Thin Section

Rhyolite

IUGS Definition ( QAPFv Chart )( QAPv Chart )

Rhyolite: A silica-rich volcanic rocks consisting of phenocrysts of quartz and alkali feldspar, often with minor plagioclase and biotite, in a microcrystalline or glassy groundmass and having the chemical composition of granite.
Photos
Typical Minerals
  • quartz
  • sanidine
  • plagioclase
  • glass