CHEMISTRY - FeS Iron sulfide
CRYSTALLOGRAPHY - Monoclinic (Pseudohexagonal)
CRYSTAL GROWTH AND HABITS - Pyrrhotite typically forms tabular or platy crystals producing a "stacked" group. It also forms rosettes and is massive granular.
COLOR AND OTHER OPTICAL PROPERTIES - Pyrrhotite is bronze yellow to brown. It quickly tarnishes with reddish hues, sometimes with iridescence. It is opaque.
HARDNESS - 3.5 - 4.5 SPECIFIC GRAVITY - 4.5 - 4.7
LUSTER - Metallic STREAK - Dark gray to black
BREAKABILITY - Pyrrhotite has an uneven to subconchoidal fracture and is brittle.
OCCURRENCE - Pyrrhotite is found with sulfides of nickel, copper and iron. It is also found in high temperature hydrothermal veins. A massive variety called troilite is known and this variety is also found in meteorites.
ASSOCIATED MINERALS - Pyrite, chalcopyrite
OTHER - Small pieces of Pyrrotite are magnetic.
NAME - From the Greek "pyrrhotes" for redness.