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Beryl

Heliodor

Yellow, golden yellow, greenish yellow

Yellow
Optical properties

Optical characteristics

Ref. index
1.565 – 1.602
Birefringence
0.005 – 0.009
Luster
Vitreous
Pleochroism
Weak Weak: yellow / pale yellow.
Fluorescence
Usually inert.
Origins

Source localities

Brazil Brazil: Minas Gerais / Paraíba / Bahia
Major

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

26.7% est. supply
Madagascar Madagascar: Ilakaka / Andranondambo region
Major

Modern major source for sapphire, garnet, beryl, quartz, tourmaline and many collector gems.

31.5% est. supply
Namibia Namibia: Erongo / Green Dragon area
Notable

Known for demantoid, spessartite and collector minerals.

20.9% est. supply
Ukraine Ukraine: Volyn / pegmatite areas
Notable

Known for beryl and collector minerals.

20.9% est. supply
Treatments

Enhancement & treatment

Heat Heat Treatment, Beryl Heating is common in several beryl varieties to improve or stabilize color. It is… Color Enhancement Irradiation, Beryl Irradiation creates or modifies color centers in beryl. Stability depends on variety and color…
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 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