Global Gemology - Rare Gems & Jewels
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CAT'S EYE TOURMALINE

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Cat's eye tourmaline and diamond pendant in platinum, accompanied by GIA Tourmaline Report
Cat's eye tourmaline and diamond pendant in platinum
Variety:  Cat's Eye
Species:  Tourmaline
​​Mohs Hardness:  7 to 7.5 out of 10
Color:  Can be any color, but usually dark bluish green to dark greenish blue.
RI:  1.62 to 1.64 Spot Reading
Birefringence:  Usually Not Detectable
SR/DR/AGG:  DR (AGG Reaction Possible)
Clarity Type:  Type III
Optic Character:  Uniaxial negative
Pleochroism:  Medium to strong, usually two tones of the gem's body color.
Spectrum:  Not diagnostic
Fluorescence:  Varies
SG:  3.06 (+0.20 / -0.06)
Routine Treatments:  None

Cat's Eye Tourmaline Facts

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Cat's eye tourmaline set in a handmade sterling silver setting
Cat's eye tourmaline ring

Tourmaline is a very attractive gem that occurs in nearly every color, even phenomenal varieties.

Cat's eye is an optical effect caused by a phenomena known as chatoyancy, caused by many tiny, parallel inclusions.

This cat's eye effect resembles the slit opening in a cat's eye, and will move across the surface of the gem interacts with direct light.

Cat's Eye Tourmaline Gallery

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  • HOME
  • ABOUT
  • SHOP
  • SERVICES
    • APPRAISALS
    • EXPERT WITNESS TESTIMONY
    • SELL YOUR JEWELRY
  • GEMOLOGY
    • GEM ENCYCLOPEDIA
    • THE ART OF GEMOLOGY
  • JEWELRY EDUCATION
    • DIAMOND FACTS
    • JEWELER DIRECTORY
    • JEWELRY PERIODS
    • POCKET WATCHES
    • NATIVE AMERICAN JEWELRY
  • GLOSSARY