Diorite (coarse-grained)

Title

Diorite (coarse-grained)

Identifier

SFM-14

Description

Hand Sample: Porphyritic (or coarse-grained phaneritic) diorite with coarse-grained white plagioclase laths up to 1cm and some black mineral. Weathering to rust-orange color.
Thin Section: 60% medium-grained interlocking rectangular plagioclase laths. Well-weathered smaller grains of quartz, biotite, and opaques fill in the spaces between laths.

Date

1/20/1969

Contributor

Western Minerals, Inc.

Spatial Coverage

St. Francois Mountains Batholith, Missouri

Accrual Method

Western Minerals, Inc.

Number of Thin Sections

1