Marlow Mountain Rhyolite

Title

Marlow Mountain Rhyolite

Identifier

SFM-18

Description

Hand Sample: Phaneritic rhyolite. 10% fine-grained phenocrysts of sanidine and quartz and 90% dark-brownish-red groundmass. Weathers to brown-orange.
Thin Section: Very weathered matrix with a few fine-grained anhedral crystals of feldspar and quartz

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