×

Alexandrite
Alexandrite

Allanite
Allanite



ADD
Compare
X
Alexandrite
X
Allanite

Alexandrite and Allanite Optical Properties

1 Optical Properties
1.1 Luster
Vitreous
Not Available
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
Agate Opal
1 3.25
1.6 Optic Character
Biaxial/+
Not Available
1.7 Crystal System
Orthorhombic
Not Available
1.8 Birefringence
0.007-0.0100.013-0.036
Achroite
0 0.296
1.9 Clarity
Transparent
Not Available

Alexandrite and Allanite Optic Character

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

Similar to their colors, Alexandrite and Allanite 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.