Bertrandite and Powellite Optical Properties

Bertrandite

Powellite

Add ⊕

1 Optical Properties

1.1 Luster

Vitreous

Greasy, Subadamantine

1.2 Pleochroism

none.

In deeply colored specimens: blue greenAnthony et al

1.3 Dispersion

NANA

0.007 1

1.4 Transparency

TransparentAnthony et al, Handbook of mineralogy (2001)

Transparent

1.5 Refractive Index

1.583-1.6141.974-1.984

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 AvailableNot Available

0 0.296

1.9 Clarity

TransparentAnthony et al

Transparent

Bertrandite and Powellite Optic Character

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

Bertrandite Vs Boulder Opal

Bertrandite Vs Bytownite

Bertrandite and Powellite Transparency

Similar to their colors, Bertrandite and Powellite 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.