Iron Tungstate
FeWO4
Chemical name
Iron Tungstate
Mineral name
Ferberite
Chemical formula
FeWO4
Crystal system
monoclinic
Crystal Class
monoclinic-prismatic (2/m)
Space Group
P 2/c
Unit cell
a [Å]:4.76
b [Å]:5.68
c [Å]:4.92
Molecular weight [g/mol]
303.69
Formula units
Z=2
Mohs hardness
4.5
Density [g/cm3]
7.4 - 7.5
Cleavage
perfect on {010}, parting on {100} and {102}
Color
black
Transparency
nearly opaque
Optical character
biaxial (+)
Refractive Index
nα=2.255; nβ=2.305; nΥ=2.414
Birefringence δ
0.1590