Red Granophyre (fine grained)

Title

Red Granophyre (fine grained)

Identifier

SFM-4

Description

Hand Sample: Holocrystalline phaneritic, porphyritic and granophyrite rich in alkali feldspar. Larger crystals or pockets of biotite and quartz also present. Rock is weathered to orange brown. Contact on one side with dark black-brown quartz-rich material. Possibly represents a roof pendant of chilled contact facies on the St. Francois Batholith
Thin Section, XPL: Fine-grained subhedral crystals. 50% quartz, 35% alkali feldspar, 5% plagioclase feldspar, 5% biotite, 5% hornblende

Date

1/20/1969

Contributor

Western Minerals, Inc

Spatial Coverage

St. Francois Mts. Batholith, Missouri at Scott's Quarry

Accrual Method

Purchased from Western Minerals, Inc.

Number of Thin Sections

1