French Mills Rhyolite
Hand Sample: Phaneritic rhyolite with fine-grained phenocrysts of quarts, feldspar and hornblende in a brownish-red groundmass. Weathers to orange-brown.
Thin Section, XPL: 50% medium-to-fine grained subhedral well-weathered plagioclase crystals, some rimmed in opaques. 50% matrix.
Western Minerals, Inc.
Is Part Of
St. Francois Mountains Batholith, Missouri
Purchased from Western Minerals, Inc
Number of Thin Sections