Stouts Creek Rhyolite (VanEast group)

Title

Stouts Creek Rhyolite (VanEast group)

Identifier

SFM-12

Description

Hand Sample: Hypocrystalline, porphyritic rhyolite. 20% subhedral to anhedral biotite, quartz, and microcline (sanidine) phenocrysts. 80% grey-brown groundmass. Massive.
Thin Section, XPL: 50% subhedral, medium and fine-grained quartz and plagioclase crystals in 50% matrix that contains opaques and quartz among other minerals. Hexagonal inclusion of very-fine-grained, subhedral, well-weathered grains of quartz, biotite, and opaques.

Date

1/20/1969

Contributor

Western Minerals, Inc

Spatial Coverage

St. Francois Mountains Batholith, Missouri

Accrual Method

Purchased from Western Minerals, Inc

Number of Thin Sections

1