×

Alunite
Alunite

Polyhalite
Polyhalite



ADD
Compare
X
Alunite
X
Polyhalite

Alunite and Polyhalite Optical Properties

Optical Properties

Luster

Vitreous, Pearly
Vitreous, Resinous

Pleochroism

-
-

Dispersion

0.020.02
0.005 1
👆🏻

Transparency

-
-

Refractive Index

1.5721.546-1.548
1 3.25
👆🏻

Optic Character

-
-

Crystal System

Trigonal
Triclinic

Birefringence

0.0200.021
0 0.296
👆🏻

Clarity

-
-

Alunite and Polyhalite Optic Character

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

Alunite and Polyhalite Transparency

Similar to their colors, Alunite and Polyhalite 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, Alunite is while Alunite is in appearance.