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BERYL (Aquamarine (Source & Market (Brazil, Pakistan, and China are…
BERYL
Aquamarine
Finest Quality - moderately strong, medium-dark blue to slightly greenish blue
Color - Small range, very slightly greenish blue, greenish blue, very strongly greenish blue, or green-blue
The gem is pleochroic, showing near-colorless and strong blue in different crystal direction
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Cut - Often emerald cut, round or oval brilliants
Aquamarine generally shows its finest, most saturated color in large sizes (over 5 cts).
Common imitation- treated blue topaz, pale blue glass, and synthetic blue spinel colored by cobalt.
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Source & Market
Brazil, Pakistan, and China are leading producers of aquamarine.
Brazil
- most important source of gem-quality aquamarine since 1811.
- Most mines locate in northeast Minas Gerais, directly from pegmatites, alluvial deposits
- 5% from Minas Gerais consists of top-quality
China
- recently became the world's leading producer of small, commercial-quality aquamarine.
- Chinese aquamarine is clean & very pale
In the late 1990s, Japan was the best market for high-quality aqua- marine. Medium to high-quality stones also sold well in Germany and Italy, and almost all grades were marketable in the US.
Treatment
Virtually all aquamarine is heat-treated to remove the yellow color component and produce a more marketable blue color.
Heat treatment is undetectable, and the treated color appears to be permanent
Most gem-quality beryl grows in pegmatites. It’s often possible to cut large stones that are almost completely free of inclusions.
Green Beryl
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Trace Element: Iron with perhaps some chromium
Color Range: Very strongly bluish green, bluish green, very slightly bluish green, green, slightly yellowish green, yellowish green or strongly yellowish green
Pink Beryl
Morganite
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Trace Element: Manganese
Color Range: pink, rose, peach & salmon
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Most of morganite comes form pegmatite mines in Minas Derais, Brazil, Afghanistan, Mozambique, Namibia
Price: Top-quality: up to 3 cts,$110 - $200 per carat
over 20 cts, price drops
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Red Beryl
Bixbite
Source: The US state of Utah is the world’s only known source of red beryl.
Rock: Found in fissures of rhyolite - a light-colored, finely grained igneous rock
Gems cut with the table parallel to the crystal’s length are more purplish red. Stones cut with the table perpendicular to the crystal’s length show a more uniform orange-red hue.
Trace Element: Manganese
Color Range: pleochroic of purple,
orange, or violet
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Since late 1990s, red beryl has been an expensive specialty stone in demand among collectors
Maxixe Beryl
Dark blue
- The beautiful color faded rapidly when the crystals were exposed to light or heat.
- Not suitable for jewelry use
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