Hand Sample: Porphyritic latite with medium-to-coarse-grained subhedral plagioclase phenocrysts in a brown-black groundmass. Thin black veins present with green margin of contact on either side.
Thin Section, XPL: Medium-grained subhedral phenocrysts of plagioclase feldspar, quartz, and microcline feldspar in a matrix that appears to be made from the same minerals. Very fine vein of greenish minerals runs through sample.
Western Minerals, Inc.
Is Part Of
St. Francois Mountains Batholith, Missouri
Purchased from Western Minerals, Inc.
Number of Thin Sections