1 Optical Properties
1.1 Luster
Waxy, Silky, Resinous, Greasy
Not Available
1.2 Pleochroism
Not Available
Sometimes strongArthur Thomas
1.3 Dispersion
1.4 Transparency
TranslucentHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
TransparentWalter Schumann, Gemstones of the world (2001) More from other references
1.5 Refractive Index
1.530-1.5752.19-2.34
1
3.25
1.6 Optic Character
Not Available
Not Available
1.7 Crystal System
Not Available
Not Available
1.8 Birefringence
Not Available0.015
0
0.296
1.9 Clarity
TranslucentHerve Nicolas Lazzarelli
TransparentWalter Schumann