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n. A usually black or banded, hard volcanic glass that displays shiny, curved surfaces when fractured and is formed by rapid cooling of lava.

n. a type of black glass produced by volcanos

adj. black

n. A kind of glass produced by volcanoes. It is usually of a black color, and opaque, except in thin splinters.

n. A volcanic rock, in a vitreous condition, and closely resembling ordinary bottle-glass in appearance and texture.

n. acid or granitic glass formed by the rapid cooling of lava without crystallization; usually dark, but transparent in thin pieces

"Glass in the form of a volcanic residue such as obsidian is found in nature."

volcanic glass   

Davidian    Floridian    Gideon    Meridian    antemeridian    didion    meridian   

flint    agate    basalt    alabaster    onyx    malachite    jade    razor-sharp    carnelian    quartz