×

Alexandrite
Alexandrite

Polyhalite
Polyhalite



ADD
Compare
X
Alexandrite
X
Polyhalite

Alexandrite and Polyhalite Optical Properties

1 Optical Properties
1.1 Luster
Vitreous
Vitreous, Resinous
1.2 Pleochroism
Not Available
Not Available
1.3 Dispersion
NANA
Fluorite Optical Properties
0.007 1
1.4 Transparency
Transparent, Transparent to nearly opaque
Not Available
1.5 Refractive Index
1.739-1.7701.546-1.548
Agate Opal
1 3.25
1.6 Optic Character
Biaxial/+
Not Available
1.7 Crystal System
Orthorhombic
Triclinic
1.8 Birefringence
0.007-0.0100.021
Achroite
0 0.296
1.9 Clarity
Transparent
Not Available

Alexandrite and Polyhalite Optic Character

Alexandrite and Polyhalite optical properties play a significant role while distinguishing these gemstones from each other. These properties are influenced by the Alexandrite 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 Alexandrite 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. Alexandrite has Biaxial/+ character.

Alexandrite and Polyhalite Transparency

Similar to their colors, Alexandrite 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, Alexandrite is Transparent and Transparent to nearly opaque while Alexandrite is Transparent and Transparent to nearly opaque in appearance.