General Information:
Chemical Formula:NaCa2(Zr,Nb)Si2O7(O,OH,F)2
Physical Properties:
Cleavage:[???] Perfect
Color:yellow, dark yellow, gray, or brown.
Density:3.42
Diaphaniety:Transparent to Translucent
Hardness:5.5-6 - Knife Blade-Orthoclase
Luminescence:Non-fluorescent.
Luster:Vitreous - Greasy
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