Fergusonite-(Y)

General Information:
 Chemical Formula:
YNbO4
 Composition:
(Molecular Weight = 245.81 gm)
Yttrium 36.17 % Y 
Niobium 37.80 % Nb
Oxygen 26.04 % O 
 Empirical Formula:
YNbO4
 IMA Status:
Approved IMA 1987
Physical Properties:
 Cleavage:
[???] Indistinct
 Color:
black, black, brown, gray, or yellow.
 Density:
4.3 - 5.8, Average = 5.05
 Diaphaniety:
Subtranslucent to opaque
 Hardness:
5.5-6 - Knife Blade-Orthoclase
 Luminescence:
Non-fluorescent.
 Luster:
Sub Metallic
 Streak:
brown
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