obsidian has definitions from the field of geology
1
[ noun ] (geology) acid or granitic glass; usually dark, but transparent in thin pieces

Used in print

(S. J. Perelman, The Rising Gorge. New York:...)

First_of_all , the six figures of the Buddha you heisted - four Siamese heads , a black obsidian statuette in the earth touching position , and a large brass figure of the Dying_Buddha on a teakwood base .

Related terms

volcanic_glass

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