"WardsSci000450"

Dark gray, with hornblende as the dominant mafic mineral.

Fine to medium-grained with biotite.

Coarse-grained, with microcline, biotite and horblende phenocrysts.

Volcanic glass with snowflakes embedded throughout.

Shiny black volcanic glass showing conchoidal fracture and some spherulites.

Coarse grained and abundant in plagioclase feldspar.

Coarse-grained plagioclase and pyroxene with some olivine.

Medium-grained with biotite.

Classic, dark; from the Columbia Plateau.

Banded volcanic glass.