1 Optical Properties
1.1 Luster
Adamantine
Vitreous, Adamantine, Vitreous, Adamantine
1.2 Pleochroism
Moderate; cochineal-red to blood-red
Strong
1.3 Dispersion
1.4 Transparency
OpaqueUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) Rarely transparentMore from other references
Transparent, Translucent, Transparent to opaque
1.5 Refractive Index
2.792-3.0871.762-1.788
1
3.25
1.6 Optic Character
Not Available
Not Available
1.7 Crystal System
1.8 Birefringence
0.295-0.2960.008-0.009
0
0.296
1.9 Clarity
OpaqueUlrich Henn and Claudio C. Milisenda
Transparent