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Sillimanite
Sillimanite



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Sillimanite
Optical Properties

Luster

Pleochroism

Dispersion

Transparency

Refractive Index

Optic Character

Crystal System

Birefringence

Clarity

 
Greasy, Subadamantine
In deeply colored specimens: blue greenAnthony et al
0.03
Transparent
1.974-1.984
-
-
-9999
Transparent
 
Vitreous, Subadamantine, Silky
Colourless to pale brown to yellow
0.02
Transparent, Translucent
1.653-1.685
-
Orthorhombic
0.020-0.022
Transparent