Pyrite
Image: <a href="//commons.wikimedia.org/wiki/User:Cccefalon" title="User:Cccefalon">CEphoto, Uwe Aranas</a> (CC BY-SA 3.0)
Mineral NamePyrite
Chemical FormulaFeS₂
Mohs Hardness6
Crystal Systemcubic
Lustermetallic
Streak Colorgreenish-black to brownish-black
Cleavageindistinct/poor
Fractureconchoidal to uneven
Specific Gravity5
Colorspale brass-yellow, gold, steel-gray, black, iridescent tarnish
Transparencyopaque
Type LocalityWorldwide, notable deposits in Spain, Peru, Italy.
Mineral GroupSulfides
Usessource of sulfur, collector's specimens, historically mistaken for gold
Associated Mineralshematite, quartz, chalcopyrite
Raritycommon
Description
A specimen featuring numerous intergrown, metallic, brass-yellow crystals of pyrite, with areas of dark, steel-gray to black, somewhat iridescent hematite crystals.
Geological Context
Pyrite commonly forms in hydrothermal veins, sedimentary rocks, and metamorphic environments, often in anoxic conditions. It is frequently associated with other sulfide minerals.
