The Golden Iron Mineral

PYRITE’S MANY CRYSTAL FORMS KEEP COLLECTORS FASCINATED

- BOB JONES

From simple cubes to complex twinned dodecahedrons, pyrite appears in over a half dozen different forms. And it is certainly found in countless deposits all over the world. Pyrite is so varied and common any collector could devote an entire collecting career to this one species. Chemically pyrite is not complicated. One molecule of pyrite is composed of one atom of iron and two atoms of sulfur, iron disulfide.

What is complex about pyrite is the many crystal forms it can take and still remain in the isometric or cubic crystal system! Some pyrite crystals differ enough to be given odd names like iron cross and oscillating cubes, pyrite suns, pyrite bars and pyritized fossils. Yet cubic pyrite’s most common and very recognizable crystal form is pyritohedron. Instead of having a square crystal face of a cube as you would expect, pyritohedron faces are five-sided. Luckily today, thanks to one important deposit in Spain, the most common form for pyrite available is simply a cube on a white marl matrix.

COMMON CUBES