Brown Mountain intrusive Rhyolite
Hand Sample: Porphyritic orange-pink rhyolite. Dominantly potassium feldspar with some black crystals. Weathers to brown-black and yellow-brown.
Thin Section, XPL: Fine-grained, well-weathered quartz and alkaline feldspar interspersed with fine-grained rectangular inclusions of mixed material. Opaques present.
Western Minerals, Inc.
Is Part Of
St. Francois Mountains Batholith, Missouri
Western Minerals, Inc
Number of Thin Sections