Pyrrhotite

Physical Properties
Chemical formula Fe1-xS
Class Sulfide
Crystal system Hexagonal
Habit Massive
Disseminated
Hexagonal plates or tabs,
often twinned (rare)
Color Yellow to reddish bronze
Hardness 4
Specific gravity 4.6
Cleavage Poor (001)
Fracture Uneven
Luster Metallic
Transparency Opaque
Streak Grey to black
after Perkins, 358

Pyrrhotite in Hand Sample

Pyrrhotite in hand sample

Further Reading

Pyrrhotite at webmineral.com

Pyrrhotite at mindat.org