General Information:
Chemical Formula:
Fe++Nb2O6
Composition:
(Molecular Weight = 337.66 gm)
Niobium 55.03 % Nb
Iron 16.54 % Fe
Oxygen 28.43 % O
Empirical Formula:
Fe2+Nb2O6
Environment:
Pegmatites, and alluvial deposits.
Locality:
M'buye Mine, Rwanda.
Name Origin:
Named after its content of the element niobium, formerly called columbium and the Latin ferrium - "iron."
Physical Properties:
Cleavage:
[010] Distinct
Color:
black or brownish black.
Density:
5.3 - 7.3, Average = 6.3
Diaphaniety:
Translucent to opaque
Habits:
Massive - Granular - Common texture observed in granite and other igneous rock., Striated - Parallel lines on crystal surface or cleavage face.,
Hardness:
6 - Orthoclase
Luminescence:
Non-fluorescent.
Luster:
Sub Metallic
Streak:
blackish brown
More details...