Dravite and Tortoiseshell Optical Properties

Dravite

Tortoiseshell

Add ⊕

1 Optical Properties

1.1 Luster

Vitreous

Not Available

1.2 Pleochroism

Very strong: pale yellow colorless

Not Available

1.3 Dispersion

0.02NA

0.007 1

1.4 Transparency

Transparent

Gemmological Tables (2004)

1.5 Refractive Index

1.614-1.6661.540-1.560

1 3.25

1.6 Optic Character

Not Available

1.7 Crystal System

Trigonal Ditrigonal Pyramidal H-M Symbol (3m) Space Group: R 3m

Not Available

1.8 Birefringence

0.014-0.032Not Available

0 0.296

1.9 Clarity

Transparent

OpaqueUlrich Henn and Claudio C. Milisenda

Dravite and Tortoiseshell Optic Character

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

Compare Blue Gemstones

Dravite Vs Gadolinium Gallium Garnet

Dravite Vs Fluorite

Dravite Vs Gahnite

Dravite and Tortoiseshell Transparency

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