Apuanite

Apuanite (IMA symbol: Apu^[1]) is a rare iron antimony mineral with the chemical formula Fe²⁺Fe³⁺₄Sb³⁺₄O₁₂S whose type locality is the Province of Lucca in Italy.^[2]

Apuanite
Cubic apuanite crystal found at its type locality
General
Category	Minerals
Formula	Fe2+Fe3+4Sb3+4O12S
IMA symbol	Apu
Identification
Color	Black
Mohs scale hardness	4-5
Luster	Metallic
Diaphaneity	Opaque
Specific gravity	5.33
Density	5.33 g/cm3 (Measured) 5.22 g/cm3 (Calculated)