"WardsSci000450"

Volcanic glass with snowflakes embedded throughout.

Dark gray, with hornblende as the dominant mafic mineral.

Coarse grained and abundant in plagioclase feldspar.

Fine to medium-grained with biotite.

Medium-grained with biotite.

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

Classic, dark; from the Columbia Plateau.

Banded volcanic glass.

Light gray, with flow structure.

Glassy; most specimens float in water.