General Information:
Chemical Formula:(Y,Na,Ca,U)1-2(Nb,Ta,Ti)2(O,OH)7
IMA Status:Approved IMA 1987
Physical Properties:
Cleavage:None
Color:dark brown or black.
Density:4.91
Diaphaniety:Translucent to Opaque
Hardness:4.5-5.5
Luster:Resinous
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