Title
Diabase Porphyry Dike
Identifier
SFM-7
Description
Hand Sample: Hypocrystalline, porphyritic, diabase with subhedral plagioclase and alkali feldspar (weathered to green) crystals approximately 1cm in length. Matrix is brown-black color. Weathered to white. Intensive weathering on one side to light brown.
Thin Section, XPL: 25% medium-grained subhedral plagioclase crystals in a matrix of green and dark green aciciular grains with low birefringence. Opaques present.
Date
1/20/1969
Contributor
Western Minerals, Inc.
Is Part Of
Spatial Coverage
St. Francois Mtns. Batholith, Missouri
Accrual Method
Purchased from Western Minerals, Inc.
Number of Thin Sections
1