Bertrandite and Dallasite Optical Properties

Bertrandite

Dallasite

Add ⊕

1 Optical Properties

1.1 Luster

Vitreous

Not Available

1.2 Pleochroism

none.

Not Available

1.3 Dispersion

NANA

0.007 1

1.4 Transparency

TransparentAnthony et al, Handbook of mineralogy (2001)

Not Available

1.5 Refractive Index

1.583-1.6141.540

1 3.25

1.6 Optic Character

Not Available

1.7 Crystal System

Orthorhombic Pyramidal H-M Symbol (mm2) Space Group: Ccm21

Not Available

1.8 Birefringence

Not Available0.008-0.010

0 0.296

1.9 Clarity

TransparentAnthony et al

Not Available

Bertrandite and Dallasite Optic Character

Bertrandite and Dallasite optical properties play a significant role while distinguishing these gemstones from each other. These properties are influenced by the Bertrandite and Dallasite 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 Bertrandite and Dallasite 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 Colorless Gems

Bertrandite Vs Boulder Opal

Bertrandite Vs Bytownite

Bertrandite Vs Boracite

Bertrandite and Dallasite Transparency

Similar to their colors, Bertrandite and Dallasite 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, Bertrandite is Handbook of mineralogy (2001) and TransparentAnthony et al while Bertrandite is Handbook of mineralogy (2001) and TransparentAnthony et al in appearance.