Porphyritic Granite Dike

Title

Porphyritic Granite Dike

Identifier

SFM-24

Description

Hand Sample: Phaneritic granite with coarse-grained phenocrysts of smokey quartz and generally smaller crystals including potassium feldspar. Weathers to orange on one side and some light-gray material on the other.
Thin Section: 25% coarse-grained quartz phenocrysts in a matrix of 40% fine-grained rectangular plagioclase laths, 30% fine-grained alkali feldspar, and 30% fine-grained 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

Geolocation