General Information:
Chemical Formula:
(Zn,Mn++,Fe++)(Fe+++,Mn+++)2O4
Composition:
(Molecular Weight = 236.54 gm)
Manganese 18.58 % Mn
Zinc 16.59 % Zn
Iron 37.78 % Fe
Oxygen 27.06 % O
Empirical Formula:
Zn0.6Mn2+0.3Fe2+0.1Fe3+1.5Mn3+0.5O4
Environment:
Zinc rich orebody weathered and later metamorphosed..
Locality:
Dominant ore mineral at Franklin and Sterling Hill, New Jersey, USA.
Name Origin:
Named after its locality.
Physical Properties:
Cleavage:
None
Color:
black or brownish black.
Density:
5.07 - 5.22, Average = 5.14
Diaphaniety:
Opaque
Habits:
Euhedral Crystals - Occurs as well-formed crystals showing good external form., Massive - Uniformly indistinguishable crystals forming large masses., Crystalline - Fine - Occurs as we ll-formed fine sized crystals.
Hardness:
5.5-6 - Knife Blade-Orthoclase
Luminescence:
None.
Luster:
Sub Metallic
Streak:
reddish brown
More details...