Property |
ferberite |
wolframite |
huebnerite |
Picture |
|
|
|
formula |
FeWO4 |
(Fe, Mn)WO4 |
MnWO4 |
WO3 content (%) |
76.3 |
76.5 |
76.6 |
Mn content (%) |
0 - 3.6 |
3.6 - 14.5 |
14.5 - 18.1 |
Fe content (%) |
18.4 - 14.7 |
14.7 - 3.7 |
3.7 - 0 |
specific gravity |
7.5gr/cc |
7.1 - 7.5 gr/cc |
7.2 - 7.3 gr/cc |
form |
well defined crystals |
irregular groups of radiating crystals |
radiating thin crystals |
color |
black |
dark grey to black |
red-brown to black |
luster |
submetallic to metallic |
submetallic to metallic |
submetallic to adamantine |
diaphaneity |
opaque to translucent |
opaque |
opaque to translucent |
streak |
dark brown |
dark brown |
red-brown to green-yellow |
crystal structure |
monoclinic |
monoclinic |
monoclinic |
cleavage |
1 direction, perfect |
1 direction, perfect |
1 direction, perfect |
fracture |
uneven |
uneven |
uneven |
hardness |
5 Mohs |
5 -5.5 Mohs |
5 Mohs |
magnetism |
feeble |
slight |
none |