Gemstone/
Origin |
Description |
Treatment |
Effects |
Care |
Cleaning |
Amethyst
(quartz) / Natural |
Purple through bluish purple |
Heat treatment |
Lightens the color of very dark amethyst; removes smoky component of color |
None |
Ultrasonic: Usually safe
Steamer: Risky
Warm Soapy Water: Safe |
Aquamarine
(beryl) / Natural |
Greenish blue through blue-green |
Heat treatment |
Produces blue from green, iron-colored material |
None |
Ultrasonic: Usually safe, unless stone contains feathers or liquid inclusions
Steamer: Usually safe, unless stone contains feathers or liquid inclusions
Warm Soapy Water: Safe |
Black Cultured Pearl
/ Organic |
Contains body colors of black, dark gray, or dark tones of blue, purple, green, or bronze |
Irradiation |
To produce "black" pearls (also gray or blue gray) from bleached pearls |
Wipe with very soft cloth after each wearing |
Ultrasonic: Never
Steamer: Never
Warm Soapy Water: Safe for more thorough cleaning (if strung, be sure string is completely dry before washing) |
| Blue Quartz / Lab Created |
Meduim sky blue |
|
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| Blue Topaz / Natural |
Very slightly greenish blue to greenish blue |
Irradiation |
Produces a blue color in irradiated stones |
Avoid heat and prolonged exposure to strong light; if radioactive (rare), avoid handling and wear |
Ultrasonic: Never
Steamer: Never
Warm Soapy Water: Safe |
Citrine
(quartz) / Natural |
Yellow through orange |
Heat treatment |
Produces citrine from amethyst |
Avoid steam |
Ultrasonic: Usually safe
Steamer: Risky
Warm Soapy Water: Safe |
| Created Ruby (synthetic corundum) / Lab Created |
Very strong orangy red |
Quench cracking (heating and then plunging it into cold water) |
Produces cracks which imitate natural breaks and fingerprint inclusions |
Avoid rough wear |
Ultrasonic: Usually safe, but never for oiled stones
Steamer: Usually safe, but never for oiled stones
Warm Soapy Water: Safe, but avoid strong detergents and vigorous scrubbing on oiled stones |
Cubic Zirconia
(synthetic) / Lab Created |
Colorless |
None |
|
None |
Ultrasonic: Safe
Steamer: Safe
Warm Soapy Water: Safe |
Cultured Pearl
/ Organic |
Translucent to opaque |
· Bleaching
· Dyeing |
· Bleach dark spots of conchiolin that show through the nacre
· To alter the body color or hide colored blemishes |
Wipe with very soft cloth after each wearing |
Ultrasonic: Never
Steamer: Never
Warm Soapy Water: Safe for more thorough cleaning (if strung, be sure string is completely dry before washing) |
Emerald
(beryl) / Natural |
Very strongly bluish green through green |
Oiling (oil may contain green dye) |
Hides flaws, improves transparency, may deepen color |
Keep away from strong solvents, heat, and ultrasonic cleaners |
Ultrasonic: Never
Steamer: Never
Warm Soapy Water: Generally safe, but avoid strong detergents and vigorous scrubbing on oiled stones |
Garnet
(pyrope) / Natural |
Red through slightly purplish red |
None known |
|
None |
Ultrasonic: Usually safe
Steamer: Risky
Warm Soapy Water: Safe |
| Iolite / Natural |
Violet-blue through slightly violet-blue |
None known |
|
None |
Ultrasonic: Risky
Steamer: Risky
Warm Soapy Water: Safe |
Mother of Pearl
(shell) / Organic |
Translucent to opaque |
Dyeing |
To produce a variety of colors |
Avoid solvents and prolonged exposure to strong light |
Ultrasonic: Risky
Steamer: Risky
Warm Soapy Water: Safe |
| Mount St. Helens / Lab Created |
Deep, clean bluish green |
|
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| Mystic Fire Topaz / Natural |
Greenish |
Coated |
Changes clear topaz to color |
Normal |
Ultrasonic: Unsafe
Steamer: Unsafe
Warm Soapy Water: Safe |
Onyx
(chalcedony) / Natural |
Solid black color |
Dyeing |
Chalcedony is dyed to practically all colors for various uses; the bands in agate and onyx accept dye differently so that a green dye, for example, may impart color to some layers and leave others white |
None |
Ultrasonic: Usually safe
Steamer: Usually safe
Warm Soapy Water: Safe |
| Peridot / Natural |
Yellowish green through greenish yellow |
No commercial treatments known |
|
None |
Ultrasonic: Risky
Steamer: Never
Warm Soapy Water: Safe |
Pink Sapphire
(corundum) / Natural |
Red through purple |
Coating with a thin film |
Creates, deepens, or changes the color of a sapphire |
Avoid abrasions |
Ultrasonic: Usually safe
Steamer: Usually safe
Warm Soapy Water: Safe |
| Pink Tourmaline / Natural |
Red-orange through reddish purple |
Irradiation |
Produces a deep pink to red to deep purple from very light pink, green, blue, or colorless |
None |
Ultrasonic: Risky
Steamer: Risky
Warm Soapy Water: Safe |
| Rhodolite Garnet / Natural |
Slightly purplish red through reddish purple |
None known |
|
None |
Ultrasonic: Usually safe
Steamer: Never
Warm Soapy Water: Safe |
Ruby
(corundum) / Natural |
Orange-red through strongly purplish red |
Heat treatment |
Removes purple or brownish color component |
None |
Ultrasonic: Usually safe, but never for oiled stones
Steamer: Usually safe, but never for oiled stones
Warm Soapy Water: Safe, but avoid strong detergents and vigorous scrubbing on oiled stones |
Sapphire
(corundum) / Natural |
Violet-blue through greenish blue |
Heat treatment |
Produces blue sapphire from milky "gueda" sapphire |
None |
Ultrasonic: Usually safe
Steamer: Usually safe
Warm Soapy Water: Safe |
| Tanvorite / Lab Created |
Deep, clean bluish/purple |
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Tanzanite
(zoisite) / Natural |
Bluish purple and violet through blue |
Heat treatment |
Produces tanzanite colors in certain crystals with initially brownish colors |
None |
Ultrasonic: Never
Steamer: Never
Warm Soapy Water: Safe |
