General Information:
Chemical Formula:
(Y,U,Fe++)(Ta,Nb)O4
IMA Status:
Approved IMA 1987
Physical Properties:
Cleavage:
[???] Imperfect
Color:
brownish black, yellowish brown, or yellow.
Density:
5.5 - 5.9, Average = 5.7
Diaphaniety:
Opaque to subtranslucent
Hardness:
5-5.5 - Apatite-Knife Blade
Luminescence:
Non-fluorescent.
Luster:
Sub Metallic
Streak:
colorless gray
More details...