Optical Properties
Luster
Vitreous
Pearly
Pleochroism
Not Available
AbsentWalter Schumann
Dispersion
Not Available
None
Transparency
Transparent, Translucent
Transparent, Transparent to translucent
Refractive Index
1.470-1.491
1.518-1.527
Optic Character
Not Available
Not Available
Crystal System
Trigonal
monoclinic
Birefringence
0.021
0.006-0.007
Clarity
Transparent
Transparent
