"WardsSci000450"

Gray andesite with phenocrysts of felspar and/or hornblende.

Classic, dark; from the Columbia Plateau.

Coarse, 'salt and pepper': dark pyroxene and light andesine. Provides perfect representation of an intermediate igneous rock.

Coarse grained and abundant in plagioclase feldspar.

Volcanic glass with snowflakes embedded throughout.