Manganese Oxide Hausmannite type
Mn2O3
Chemical name
Manganese Oxide Hausmannite type
Mineral name
Hausmannite
Chemical formula
Mn2O3
Crystal system
tetragonal
Crystal Class
ditetragonal-dipyramidal (4/m 2/m 2/m)
Space Group
I4_1/amd
Unit cell
a [Å]:5.76
b [Å]:5.76
c [Å]:9.44
Formula units
Z=4
Twinning
common on (112)
Mohs hardness
5.5
Density [g/cm3]
4.7 - 4.84
Cleavage
perfect on {001}, indistinct on {112}, {011}
Fracture / Tenacity
brittle, uneven
Color
brownish black, grayish
Streak
dark reddish brown
Transparency
opaque, transparent on thin edges
Optical character
uniaxial (-)
Refractive Index
nω=2.15; nε=2.46
Birefringence δ
0.310