Luster
Vitreous
-
Pleochroism
Weak or absentWalter Schumann
O = brownish red; E = yellowish red
Dispersion
0.010.05
0.005
1
👆🏻
Transparency
Transparent, Translucent, Transparent to translucent
OpaqueHerve Nicolas Lazzarelli
Refractive Index
1.53-1.552.690-3.220
1
3.25
👆🏻
Optic Character
-
-
Crystal System
Triclinic
Trigonal
Birefringence
0.007-0.0100.280
0
0.296
👆🏻
Clarity
Transparent to translucent
OpaqueHerve Nicolas Lazzarelli