Pyrite

Sample of several euhedral cubic Pyrite crystals embedded on a substrate. Pyrite crystals are brass-yellow and some crystal faces show parallel striations. Largest Pyrite crystal size: 1.6 cm x 1.6 cm x 1.4 cm. Pyrite (FeS2) can be pale yellow or brass-yellow that is often tarnished with brown film and sometimes iridescent. Lustre is metallic and streak is greenish black. Hardness is 6 to 6 1/2. Pyrite usually occurs as cubes and pyritohedrons with parallel stritaitons along the crystal faces. Pyrite can also occur as octahedrons, nodules, fine to coarse granular or fibrous.