Opal and Dumortierite Optical Properties

Opal

Dumortierite

Add ⊕

1 Optical Properties

1.1 Luster

Vitreous, Pearly

Vitreous

1.2 Pleochroism

None

Strong; X = deep blue or violet; Y = yellow to red-violet or nearly colorless; Z = colorless or very pale blue

1.3 Dispersion

Albite Optical ..

⊕

▶

▼

None

Rank: N/A (Overall)▶

None

Rank: N/A (Overall)▶

▲

Fluorite Optical Properties

⊕

▶

0.044 (Anglesite Opt..)

◀ ▶ ADD ⊕

1.4 Transparency

Transparent, Translucent, Transparent to translucent

Translucent, Translucent to opaque

1.5 Refractive Index

1.37-1.52

1.669-1.723

1.6 Optic Character

Not Available

1.7 Crystal System

Trigonal

Orthorhombic

1.8 Birefringence

Not Available

0.011-0.037

1.9 Clarity

Transparent

Translucent

Opal and Dumortierite Optic Character

Opal and Dumortierite optical properties play a significant role while distinguishing these gemstones from each other. These properties are influenced by the Opal and Dumortierite 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 Opal and Dumortierite 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 Semi Precious Gemstones

Opal Vs Alexandrite

Opal Vs Amethyst

Opal Vs Lehsunia

Opal and Dumortierite Transparency

Similar to their colors, Opal and Dumortierite 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, Opal is Translucent, Transparent and Transparent to translucent while Opal is Translucent, Transparent and Transparent to translucent in appearance.