General Information:
Chemical Formula:
(Ta,Nb,Sn,Mn,Fe)16O32
IMA Status:
Approved IMA 1963
Physical Properties:
Cleavage:
None
Color:
dark brown, reddish brown, black, or black brown.
Density:
7.19 - 7.36, Average = 7.27
Hardness:
6 - Orthoclase
Luster:
Sub Metallic
Streak:
brown
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