Charoite and Sillimanite Optical Properties
Luster
Pearly, Fibrous, Chatoyant
Vitreous, Subadamantine, Silky
Pleochroism
NilArthur Thomas
Colourless to pale brown to yellow
Dispersion
Not Available
Not Available
Transparency
Translucent
Transparent, Translucent
Refractive Index
1.545-1.560
1.653-1.685
Optic Character
Not Available
Not Available
Crystal System
Triclinic
Orthorhombic
Birefringence
0.009
0.020-0.022
Clarity
Translucent
Transparent
Charoite and Sillimanite Optic Character
Charoite and Sillimanite optical properties play a significant role while distinguishing these gemstones from each other. These properties are influenced by the Charoite and Sillimanite 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 Sillimanite 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 Sillimanite Transparency
Similar to their colors, Charoite and Sillimanite 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.