Luster
Vitreous, Silky
Vitreous
Pleochroism
Extreme
Absent
Transparency
Translucent
Transparent, Translucent, Transparent to translucent
Refractive Index
1.580
1.73
Crystal System
Monoclinic Prismatic H-M Symbol (2/m) Space Group: C 2/c
Isometric
Birefringence
-9999
-9999
Clarity
Translucent
TransparentUlrich Henn and Claudio C. Milisenda