Hausmannite
Chemical Formula	Mn2+Mn3+2O4
Species	Oxides & Hydroxides
Crystal System	Tetragonal
Mohs Scale	5
Specific Gravity	4.7-4.84
Color	Brownish black, Grayish.
Streak	dark reddish brown
Luster	Sub-Metallic
Cleavage	Very Good nearly perfect; and indistinct.
Fracture	Irregular/Uneven
Crystal Habit：Massive - Granular - Common texture observed in granite and other igneous rock. Pseudo Octahedral - Crystals show an octahedral outline.