pyrite

Pyr"ite, n.; pl. Pyrites. Etym: [Cf. F. pyrite. See Pyrites.] (Min.) Defn: A common mineral of a pale brass-yellow color and brilliant metallic luster, crystallizing in the isometric system; iron pyrites; iron disulphide. Hence sable coal his massy couch extends, And stars of gold the sparkling pyrite blends. E. Darwin.

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