Chemistry:Rainbow Pyrite

thumb|Rainbow pyrite from Russia

Rainbow pyrite, also known as iridescent pyrite, is a variety of pyrite (FeS₂) which is colored the colors of the rainbow by small traces of molybdenum, and its iridescence is caused by oxidation. Rainbow pyrite occurs in spherical concretions, often with internal shrinkage fractures. Iridescent pyrite was discovered near the Volga river in Russia.

Discovery and sources

Rainbow pyrite is a recently discovered mineral. It was discovered near Ulyanovsk, Russia, on the Volga river. Although rainbow pyrite can be found throughout many locations in the world, including Peru, Bolivia, Mexico, and South Africa, iridescent pyrite has only so far been found in only one location, near the Volga river in Russia.