Luster
Vitreous, Adamantine
Vitreous
Pleochroism
None
Weak: yellowish brown yellowAnthony et al
Transparency
Transparent, Transparent to translucent
-
Refractive Index
1.730-1.895
1.509-1.541
Crystal System
Trigonal
-
Birefringence
-9999
0.030
Clarity
Transparent
TransparentUlrich Henn and Claudio C. Milisenda