Luster
Vitreous
Vitreous
Pleochroism
Weak or absentWalter Schumann
X = red; Y = yellow-orange; Z = emerald-green
Dispersion
0.010.02
0.005
1
👆🏻
Transparency
Transparent, Translucent, Transparent to translucent
Transparent, Translucent, Transparent to translucent
Refractive Index
1.53-1.551.746-1.763
1
3.25
👆🏻
Optic Character
-
Biaxial/+
Crystal System
Triclinic
Orthorhombic
Birefringence
0.007-0.0100.007-0.013
0
0.296
👆🏻
Clarity
Transparent to translucent
Transparent