Optical Properties
Luster
Adamantine
Not Available
Pleochroism
Weakly pleochroic with O reddish and E greenish in thick sections.
Strong: dark blue light blueWalter Schumann
Dispersion
Not Available
0.02
22
Transparency
Gemmological Tables (2004) More from other references
Transparent, Translucent
Refractive Index
2.117-2.145
1.614-1.666
Optic Character
Not Available
Not Available
Crystal System
tetragonal
Not Available
Birefringence
0.027
0.014-0.040
Clarity
TransparentUlrich Henn and Claudio C. Milisenda
Transparent
