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Chrysoberyl

Cat’s Eye Chrysoberyl

Chatoyant chrysoberyl with sharp cat’s eye

Brown Green Yellow
Optical properties

Optical characteristics

Ref. index
1.746 – 1.755
Birefringence
0.008 – 0.01
Luster
Vitreous
Pleochroism
Weak Variable depending on transparency, orientation, and variety.
Fluorescence
Variable to inert.
Origins

Source localities

Sri Lanka Sri Lanka: Ratnapura / Elahera
Premium ★ Top Source

Classic Ceylon source for sapphire and many alluvial gems; known for bright colors and good clarity.

46.5% est. supply
Brazil Brazil: Minas Gerais / Paraíba / Bahia
Major

Major source for beryl, tourmaline, quartz, topaz, chrysoberyl and rare minerals.

31.5% est. supply
India India: Rajasthan / Odisha / Karnataka
Notable

Historic and modern source for garnet, moonstone, corundum and other gems.

22% est. supply
Inclusions

Inclusions & features

Crystals Crystal Inclusions Under 10x loupe: solid, well-formed mineral crystals trapped inside the host gem. They may… Synthetic Curved Growth Striae, Synthetic ID Under 10x loupe in immersion: curved parallel lines flowing through the stone in sweeping… Fractures Feathers and Fractures Under 10x loupe: irregular internal surfaces that catch light and appear bright, wing-like, or… Fractures Fingerprint Inclusions Under 10x loupe: curved or wavy lines of tiny dots forming patterns that look… Needles Growth Tubes, Rain Inclusions Under 10x loupe: long thin hollow channels running parallel to each other and to… Clouds Pinpoint Clouds Under 10x loupe: concentrations of extremely tiny bright dots that individually are too small… Multiphase Two-Phase Inclusions Under 10x loupe: a transparent irregular cavity containing both a liquid phase and a…
Identification

Instruments used

Dichroscope Reveals pleochroism, instantly eliminates singly-refractive stones Immersion Microscope See every internal detail clearly, the professional standard 10x Loupe Your most-used instrument, start every examination here Polariscope Determines single vs. double refraction, quick and conclusive Refractometer Measures refractive index, the backbone of gem identification UV Lamp, Long Wave and Short Wave Fluorescence exposes treatments, synthetics, and origin Fiber Optic Halogen Illuminator Intense pinpoint white light for inclusions, fractures, and treatment clues High CRI Penlight Tiny concentrated white spot for field checks, inclusions, fire, and fractures