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Pearl
Pearl

Sillimanite
Sillimanite



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Pearl
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Sillimanite

Pearl and Sillimanite Optical Properties

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Optical Properties

Luster

Pearly
Vitreous, Subadamantine, Silky

Pleochroism

-
Colourless to pale brown to yellow

Dispersion

0.030.02
0.005 1
👆🏻

Transparency

Translucent, Opaque
Transparent, Translucent

Refractive Index

1.52-1.661.653-1.685
1 3.25
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Optic Character

-
-

Crystal System

Orthorhombic
Orthorhombic

Birefringence

0.1560.020-0.022
0 0.296
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Clarity

Translucent
Transparent

Pearl and Sillimanite Optic Character

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

Pearl and Sillimanite Transparency

Similar to their colors, Pearl 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, Pearl is Translucent and Opaque while Pearl is Translucent and Opaque in appearance.