Pyrite

[Sarah]

A common mineral of a pale brass-yellow color and brilliantmetallic luster, crystallizing in the isometric system; iron pyrites;iron disulphide.Hence sable coal his massy couch extends, And stars of gold thesparkling pyrite blends. E. Darwin.

[Sarah]

A brass-colored mineral, FeS2, occurring widely, used as an iron ore and used in producing sulfur dioxide for sulfuric acid. Also known as fool's gold because it looked like gold and people used to think it was.

[Zipporah Schumaker]

A shiny yellow mineral consisting of iron disulfide and typically occurring as intersecting cubic crystals.