Thulite and Umbalite Optical Properties

Thulite

Umbalite

Add ⊕

1 Optical Properties

1.1 Luster

Vitreous

Not Available

1.2 Pleochroism

Present

Not Available

1.3 Dispersion

NA0.02

0.007 1

1.4 Transparency

Opaque, Translucent, Opaque . May be translucent in thin backlit sections.

TransparentGemdat.org, Management Team (2012)

1.5 Refractive Index

1.6951.730-1.820

1 3.25

1.6 Optic Character

Not Available

1.7 Crystal System

Orthorhombic

Not Available

1.8 Birefringence

0.006-0.018Not Available

0 0.296

1.9 Clarity

OpaqueHerve Nicolas Lazzarelli

TransparentGemdat.org

Thulite and Umbalite Optic Character

Thulite and Umbalite optical properties play a significant role while distinguishing these gemstones from each other. These properties are influenced by the Thulite and Umbalite 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 Thulite and Umbalite 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 Red Gemstones

Thulite Vs Uvite

Thulite Vs Tugtupite

Thulite Vs Verdite

Thulite and Umbalite Transparency

Similar to their colors, Thulite and Umbalite 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, Thulite is Opaque, Opaque . May be translucent in thin backlit sections. and Translucent while Thulite is Opaque, Opaque . May be translucent in thin backlit sections. and Translucent in appearance.