Luster
Vitreous
-
Pleochroism
Weak or absentWalter Schumann
Definite: brown reddish-brownWalter Schumann
Dispersion
0.010.01
0.005
1
👆🏻
Transparency
Transparent, Translucent, Transparent to translucent
Transparent, Translucent
Refractive Index
1.53-1.551.544-1.553
1
3.25
👆🏻
Optic Character
-
-
Crystal System
Triclinic
-
Birefringence
0.007-0.0100.009
0
0.296
👆🏻
Clarity
Transparent to translucent
Transparent