×

Tortoiseshell
Tortoiseshell

Alexandrite
Alexandrite



ADD
Compare
X
Tortoiseshell
X
Alexandrite

Tortoiseshell and Alexandrite Optical Properties

Optical Properties

Luster

-
Vitreous

Pleochroism

-
-

Dispersion

0.010.02
0.005 1
👆🏻

Transparency

-
Transparent, Transparent to nearly opaque

Refractive Index

1.540-1.5601.739-1.770
1 3.25
👆🏻

Optic Character

-
Biaxial/+

Crystal System

-
Orthorhombic

Birefringence

-99990.007-0.010
0 0.296
👆🏻

Clarity

OpaqueUlrich Henn and Claudio C. Milisenda
Transparent

Tortoiseshell and Alexandrite Optic Character

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

Tortoiseshell and Alexandrite Transparency

Similar to their colors, Tortoiseshell and Alexandrite 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, Tortoiseshell is while Tortoiseshell is in appearance.