"Gary K. benson"

Compact Plant Fiber Masses.

Dark gray, composed mostly of pyroxene and olivine.

Gray and poorly sorted, with a gritty texture.

Coarse-grained plagioclase and pyroxene with some olivine.

Dark gray, with hornblende as the dominant mafic mineral.

White and black bands of quartz, feldspar, and biotite; typical foliation.

Pink and gray bands, with biotite; shows good foliation.

Fine to medium-grained with biotite.

Medium-grained with biotite.

Buff, coarse, crystalline “Austin Marble” with shell casts and molds.

Light gray, fine-grained, well-foliated, schistose.

Gray-to-brown basaltic, with over 50% vesicles.

Black, fissile; commonly with carbonized fossil plant impressions.

Chlorite-mica with perfect slaty cleavage.

Dark, coarse-grained, and composed chiefly of hornblende.

Red, medium, to coarse-grained iron oxide cement; shows hematite bands.