Charoite and Cryolite Optical Properties
Luster
Pearly, Fibrous, Chatoyant
  
Vitreous, Greasy, Pearly
  
Pleochroism
NilArthur Thomas
  
colorless.
  
Dispersion
Not Available
  
Not Available
  
Transparency
Translucent
  
Gemmological Tables (2004) More from other references
  
Refractive Index
1.545-1.560
  
1.338-1.339
  
Optic Character
Not Available
  
Not Available
  
Crystal System
Triclinic
  
monoclinic
  
Birefringence
0.009
  
0.001
  
Clarity
Translucent
  
TransparentUlrich Henn and Claudio C. Milisenda
  
Charoite and Cryolite Optic Character
Charoite and Cryolite optical properties play a significant role while distinguishing these gemstones from each other. These properties are influenced by the Charoite and Cryolite Physical Properties like crystallographic symmetry, pleochroism,etc. in the crystal. Some of the optical properties are refractive index, luster, optic character, pleochroism etc. Prominent among these is Charoite and Cryolite optic character. You might have noticed your gemologist rotating the gemstone while testing it. Rotating a gemstone along its optic axis helps in determining its optic character.
Charoite and Cryolite Transparency
Similar to their colors, Charoite and Cryolite transparency can also be used as criteria for their primary identification. Although transparency cannot be the only criteria for gemstone identification, it can efficiently used in gemstone grading. Talking about their transparency, Charoite is Translucent while Charoite is Translucent in appearance.