Zoisite and Cordierite Iolite Optical Properties

Zoisite

Cordierite Iolite

Add ⊕

1 Optical Properties

1.1 Luster

Vitreous

1.2 Pleochroism

X = pale pink to red-violet; Y = nearly colorless to bright pink or deep blue; Z = pale yellow to yellow-green

Strong trichroism: colorless to yellowish

1.3 Dispersion

0.020.02

0.007 1

1.4 Transparency

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

Transparent

1.5 Refractive Index

1.685-1.7071.542-1.578

1 3.25

1.6 Optic Character

Not Available

Biaxial/+

1.7 Crystal System

Orthorhombic

Not Available

1.8 Birefringence

0.006-0.0180.008-0.012

0 0.296

1.9 Clarity

Transparent

Zoisite and Cordierite Iolite Optic Character

Zoisite and Cordierite Iolite optical properties play a significant role while distinguishing these gemstones from each other. These properties are influenced by the Zoisite and Cordierite Iolite 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 Zoisite and Cordierite Iolite 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. Cordierite Iolite has Biaxial/+ character.

Compare Brown Gemstones

Zoisite Vs Sphene

Zoisite Vs Sunstone

Zoisite Vs Tourmaline Bi Color

Zoisite and Cordierite Iolite Transparency

Similar to their colors, Zoisite and Cordierite Iolite 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, Zoisite is Opaque . May be translucent in thin backlit sections., Translucent and Transparent while Zoisite is Opaque . May be translucent in thin backlit sections., Translucent and Transparent in appearance.