Tanzanite and Onyx Optical Properties

Tanzanite

Onyx

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1 Optical Properties

1.1 Luster

Vitreous

1.2 Pleochroism

Present

Not Available

1.3 Dispersion

0.03NA

0.007 1

1.4 Transparency

Transparent, Translucent, Transparent to translucent

Translucent, Opaque, Translucent to opaque

1.5 Refractive Index

1.685-1.7071.530-1.543

1 3.25

1.6 Optic Character

Not Available

1.7 Crystal System

Orthorhombic

Trigonal

1.8 Birefringence

0.006-0.018Not Available

0 0.296

1.9 Clarity

TransparentUlrich Henn and Claudio C. Milisenda

OpaqueHerve Nicolas Lazzarelli

Tanzanite and Onyx Optic Character

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

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Tanzanite and Onyx Transparency

Similar to their colors, Tanzanite and Onyx 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, Tanzanite is Translucent, Transparent and Transparent to translucent while Tanzanite is Translucent, Transparent and Transparent to translucent in appearance.