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Organic

Pearl

Nacreous organic gem from mollusks

Black Pink White
Optical properties

Optical characteristics

Ref. index
1.52 – 1.69
Luster
Pearly / nacreous
Pleochroism
None Variable depending on transparency, orientation, and variety.
Fluorescence
Variable to inert.
Origins

Source localities

Japan Japan: Itoigawa jade area
Premium ★ Top Source

Classic Japanese jadeite source.

34.2% est. supply
French Polynesia French Polynesia: Tahiti pearl farms
Premium ★ Top Source

Known for black Tahitian cultured pearls.

29% est. supply
Australia Australia: New South Wales / Queensland fields
Commercial

Commercial sapphire and opal source; many darker blue to blue-green sapphires.

6.2% est. supply
Indonesia Indonesia: pearl and coral localities
Notable

Known for cultured pearls and coral-related material.

15.4% est. supply
China China: Xinjiang / Yunnan / Hubei
Notable

Known for jade, turquoise, quartz and multiple gem deposits.

15.4% est. supply
Treatments

Enhancement & treatment

Color Enhancement Dyeing Dyeing artificially improves color in porous or fractured materials. Durability varies and disclosure is… Color Enhancement Bleaching Bleaching removes unwanted color or stains. Acceptance depends on gem type, extent, and market… Color Enhancement Dyeing, Pearls Dyeing changes pearl body color to imitate naturally colored pearls or create fashion colors.… Assembled Assembled Stones, Doublets and Triplets Assembled stones combine separate materials to imitate a single gem or enhance appearance. They…
Inclusions

Inclusions & features

Crystals Crystal Inclusions Under 10x loupe: solid, well-formed mineral crystals trapped inside the host gem. They may… 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… 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 Hydrostatic Scale Measures specific gravity, works even on opaque stones 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