Home
Gemstones


Sillimanite and Sugilite Optical Properties


Sugilite and Sillimanite Optical Properties


Optical Properties

Luster
Vitreous, Subadamantine, Silky   
Vitreous   

Pleochroism
Colourless to pale brown to yellow   
Weak   

Dispersion
Not Available   
Not Available   

Transparency
Transparent, Translucent   
Translucent   

Refractive Index
1.653-1.685   
1.607-1.612   

Optic Character
Not Available   
Not Available   

Crystal System
Orthorhombic   
Hexagonal   

Birefringence
0.020-0.022   
0.003   

Clarity
Transparent   
Translucent   

Benefits >>
<< Physical Properties

Sillimanite and Sugilite Optic Character

Sillimanite and Sugilite optical properties play a significant role while distinguishing these gemstones from each other. These properties are influenced by the Sillimanite and Sugilite 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 Sillimanite and Sugilite 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.

Compare Blue Gemstones

Sillimanite and Sugilite Transparency

Similar to their colors, Sillimanite and Sugilite 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, Sillimanite is Translucent and Transparent while Sillimanite is Translucent and Transparent in appearance.

Blue Gemstones

Blue Gemstones


Compare Blue Gemstones