Pȳ-rī'tēs, n.

n. (Min.) A combination of sulphur with iron, copper, cobalt, or nickel, presenting a white or yellowish metallic luster.

☞ The term was originally applied to the sulphuret of iron, in allusion to its giving sparks with steel. The sulphurets of other metals, or those of copper, not presenting the colors stated, are not called pyrites. Dana.

Common pyrites, the bi-sulphuret of iron. — Magnetic pyrites, a yellowish or reddish sulphuret of iron, having a metallic luster, and capable of being attracted by the magnet; pyrrhotine. — White iron pyrites, a variety of iron pyrites containing a small proportion of arsenic; marcasite. — Yellow or copper pyrites, the sulphuret of copper and iron.