Information and recommendations for further processing
Alexandrite Amethyst Aquamarine Beryl Chrysoberyl Citrine Diamond Garnet Grossular
Iolite Mali Garnet Mandarin Garnet Moonstone Morganite Paraiba Tourmaline
Peridot Rhodolite Royal Purple Garnet Rubellite Emerald Spinel Tanzanite
Topaz Tsavorite Tourmaline
Alexandrite
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Product information |
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Stone type | Alexandrite |
Common types of finishing | Usually none |
Birthstone of the month | June |
Gemstone group | Chrysoberyl |
Designation of the best colour in trade | / |
Mohs hardness | 8,5 |
Origin | Brazil, Madagascar, Sri Lanka, Russia, Zimbabwe, Tanzania, India |
Processing recommendations* | |
Ultrasound sensitivity | Usually none |
Reaction to steam | Usually none |
Reaction to heat | Usually none |
Chemical Reaction | Usually none |
Amethyst
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Stone type | Amethyst |
Common types of finishing | Heating |
Birthstone of the month | February |
Gemstone group | Quartz |
Designation of the best colour in trade | Dark purple/purple |
Mohs hardness | 7 |
Origin | Brazil, South Africa, Russia, USA, India, Australia, Mexico, Zambia, Madagascar, Namibia |
Processing recommendations* | |
Ultasound sensitivity | Usually none |
Reaction to steam | Risky |
Reaction to heat | Color change may occur with heat |
Chemical reaction | Hydrofluoric acid, ammonium fluoride |
Aquamarine
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Stone type | Aquamarine |
Common types of finishing | Heating |
Birthstone of the month | March |
Gemstone group | Beryl |
Designation of the best colour in trade | "Santa Maria" or AAA |
Mohs hardness | 7,5 - 8 |
Origin | Brazil, South Africa, USA, Tanzania, Madagascar, Pakistan, Russia, Afghanistan, Australia, India |
Processing recommendations* |
|
Ultrasound sensitivity | Usually none |
Reaction to steam | Usually none |
Reaction to heat | Usually none |
Chemical reaction | Hydrofluoric acid |
Beryl
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Stone type | Beryl |
Common types of finishing |
Heating |
Birthstone of the month |
None |
Gemstone group |
Beryl |
Designation of the best color in trade |
Dark colour |
Mohs hardness |
7,5 - 8 |
Origin | Colombia, Brazil, Zimbabwe, Tanzania, Nigeria, South Africa, India, Russia, Australia, USA |
Processing recommendations* |
|
Ultrasound sensitivity | Usually none |
Reaction to steam | Usually none |
Reaction to heat | Usually none |
Chemical reaction | Hydrofluoric acid |
Chrysoberyl
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Stone type | Chrysoberyl |
Common types of finishing | Heating |
Birthstone of the month | June |
Gemstone group | Chrysoberyl |
Designation of the best colour in trade | Neon yellow |
Mohs hardness | 7,5 - 8 |
Origin | Brazil, India, Madagascar, Myanmar, Sri Lanka, Tanzania, Simbabwe, USA, Russia |
Processing recommendations* |
|
Ultrasound sensitivity | Usually none |
Reaction to steam | Usually none |
Reaction to heat | Usually none |
Chemical reaction | Usually none |
Citrine
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Stone type | Citrine |
Common types of finishing | Heating |
Birthstone of the month | November |
Gemstone Group | Quartz |
Designation of the best colour in trade | Golden yellow or orange |
Mohs hardness | 7 |
Origin | Brazil, USA, South Africa, Zimbabwe, Madagascar, India, Australia, Russia |
Processing recommendations* |
|
Ultrasound sensitivity | Usually none |
Reaction to steam | Risky |
Reaction to heat | Color change may occur with heat |
Chemical reaction | Hydrofluoric acid, ammonium fluoride |
Diamond
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Stone type | Diamond |
Common types of finishing | Usually none |
Birthstone of the month | April |
Gemstone group | Diamond |
Designation of the best colour in trade | River plus (D) |
Mohs hardness | 10 |
Origin | Botswana, Russia, South Africa, Namibia, Australia, Namibia, Brazil, Canada, India |
Processing recommendations* | |
Ultrasound sensitivty | Usually none |
Reaction to steam | Usually none |
Reaction to heat | Usually none |
Chemical reaction | Usually none |
Garnet, Mandarin Garnet, Mali Garnet, Royal Purple Garnet
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Stone type | Garnet |
Common types of finishing | Usually none |
Birthstone of the month | January |
Gemstone group | Garnet |
Designation of the best colour in trade | / |
Mohs hardness | 7 - 7,5 |
Origin | South Africa, Madagascar, Kenia, USA, Mexico, India, Sri Lanka, Tanzania, Brazil, Thailand |
Processing recommendations* |
|
Ultrasound sensitivity | Usually none |
Reaction to steam | Risky |
Reaction to heat | Usually none |
Chemical reaction | Hydrofluoric acid |
Grossular
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Stone type | Grossular |
Common types of finishing | Usually none |
Birthstone of the month | None |
Gemstone group | Garnet |
Designation of the best colour in trade | Intesiv mint |
Mohs hardness | 7 - 7,5 |
Origin | Tanzania, Mali, Kenia, Pakistan, Sri Lanka, Mexico |
Processing recommendations* |
|
Ultrasound sensitivity | Usually none |
Reaction to steam | Risky |
Reaction to heat | Usually none |
Chemical reaction | Hydroflouric acid |
Iolite
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Stone type | Iolite |
Common types of finishing | Usually none |
Birthstone of the month | None |
Gemstone group | Iolite |
Designation of the best colour in trade | Medium dark greyish/violet colour |
Mohs hardness | 7 - 7,5 |
Origin | Myanmar, Madagascar, Namibia, India, Sri Lanka, Tanzania, Canada, USA |
Processing recommendations* | |
Ultrasound sensitivity | Risky |
Reaction to steam | Risky |
Reaction to heat | Fusible |
Chemical reaction | Attacked by acids |
Moonstone
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Stone type | Moonstone |
Common types of finishing | Usually none |
Birthstone of the month | June |
Gemstone group | Feldspar |
Designation of the best colour in trade | Adularescence |
Mohs hardness | 6 - 6,5 |
Origin | Australia, Brazil, India, Madagascar, Mexico, Sri Lanka, Tanzania, USA |
Processing recommendations* |
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Ultrasound sensitivity | Never use |
Reaction to steam | Never use |
Reaction to heat | Poor |
Chemical reaction | Hydrofluoric acid |
Morganite
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Stone type | Morganite |
Common types of finishing | Neutrons, gamma or electrodes irradiated and heated if necessary |
Birthstone of the month | None |
Gemstone group | Beryl |
Designation of the best colour in trade | Light/medium pink |
Mohs hardness | 7,5 - 8 |
Origin | Brazil, Colombia, South Africa, Madagascar, USA |
Processing recommendations* |
|
Ultrasound sensitivity | Risky |
Reaction to steam | Risky |
Reaction to heat | Poor - should never be heated |
Chemical reaction | Hydrofluoric acid and solvents |
Paraiba Tourmalin
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Stone type | Paraiba Tourmaline |
Common types of finishing | Heating |
Birthstone of the month | None |
Gemstone group | Tourmaline |
Designation of the best colour in trade | Neonblue |
Mohs hardness | 7 - 7,5 |
Origin | Brazil, Nigeria, Mozambique |
Processing recommendations* |
|
Ultrasound sensitivity | Risky |
Reaction to steam | Usually none |
Reaction to heat | May cause color change and fracturing |
Chemical reaction | Usually none |
Peridot
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Stone type |
Peridot |
Common types of finishing | Usually none |
Birthstone of the month |
August |
Gemstone group | Peridot |
Designation of the best colour in trade | mid-dark yellow/green |
Mohs hardness |
6,5 - 7 |
Origin |
Myanmar, Pakistan, China, Egypt, Kenya, Sri Lanka, USA |
Processing recommendations* |
|
Ultrasound sensitivity |
Risky |
Reaction to steam |
Never use |
Reaction to heat |
Heat treatment can cause cracks |
Chemical reaction |
Sulfuric acid, hydrochloric acid, pickling solution |
Rhodolite
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Stone type |
Rhodolite |
Common types of finishing |
Usually none |
Birthstone of the month |
None |
Gemstone group |
Garnet |
Designation of the best colour in trade |
Purple |
Mohs hardness |
6,5 - 7,5 |
Origin | Tanzania, USA, Kenia, India, Sri Lanka, Tanzania, Madagascar |
Processing recommendations* |
|
Ultrasound sensitivity |
Usually none |
Reaction to steam |
Risky |
Reaction to heat |
Usually none |
Chemical reaction |
Hydrofluoric acid |
Rubellite
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Stone type |
Rubellite |
Common types of finishing |
Heating treatment |
Birthstone of the month |
None |
Gemstone group |
Turmaline |
Designation of the best colour in trade |
Rasperry red to ruby |
Mohs hardness |
7 - 7,5 |
Origin |
Nigeria, Mozambique, Brazil, Madagascar, Kenia, Tanzania, USA, Afghanistan |
Processing recommendations* |
|
Ultrasound sensitivity |
Risky |
Reaction to steam |
Risky |
Reaction to heat |
Can cause color change |
Chemical reaction |
Usually none |
Emerald
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Stone type |
Emerald |
Common types of finishing |
Filling cracks with oil, wax or other substances (except glass or plastic) to improve the appearance |
Birthstone of the month |
None |
Gemstone group |
Beryl |
Designation of the best colour in trade | Mid-dark green |
Mohs hardness |
7,5 - 8 |
Origin | Afghanistan, Brazil, Columbia, India, Pakistan, Russia, Samira, Simbabwe |
Processing recommendations* |
|
Ultrasound sensitivity |
Risky |
Reaction to steam |
Never use |
Reaction to heat |
No heating recommended |
Chemical reaction |
Hydrofluoric acid |
Spinel
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Stone type |
Spinel |
Common types of finishing |
usually none |
Birthstone of the month |
None |
Gemstone group |
Spinel |
Designation of the best colour in trade |
pink/red-red or cobaltblue |
Mohs hardness |
8 |
Origin |
Madagascar, Tanzania, Sri Lanka, Afghanistan, Australia, Brazil, Nepal, Nigeria, Tajikistan, Thailand, USA |
Processing recommendations* |
|
Ultrasound sensitivity |
Usually none |
Reaction to steam |
Usually none |
Reaction to heat |
Usually none |
Chemical reaction |
Usually none |
Tanzanite
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Stone type |
Tanzanite |
Common types of finishing |
Heat |
Birthstone of the month |
December |
Gemstone group |
Zoisit |
Designation of the best colour in trade |
AAA oder darkblue without lila |
Mohs hardness |
6 - 7 |
Origin |
Tanzania |
Processing recommendations* |
|
Ultrasound sensitivity |
Never use |
Reaction to steam |
Never use |
Reaction to heat |
Rapid changes in temperature can cause cracks |
Chemical reaction |
Hydrofluoric& Hydrochloric acid |
Topaz
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Stone type |
Topaz |
Common types of finishing |
Neutron, gamma or electrode irradiation and possibly heating |
Birthstone of the month |
None |
Gemstone group |
Topaz |
Designation of the best colour in trade |
Imperial Topaz (orange/red) |
Mohs hardness |
8 |
Origin | Brazil, Myanmar, Afghanistan, Australia, Zimbabwe, Namibia, Nigeria, Russia, Sri Lanka |
Processing recommendations* |
|
Ultrasound sensitivity |
Never use |
Reaction to steam |
Never use |
Reaction to heat |
May cause color change |
Chemical reaction |
Usually none |
Tsavorite
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Stone type |
Tsavorite |
Common types of finishing |
Usually none |
Birthstone of the month |
None |
Gemstone group |
Garnet |
Designation of the best colour in trade |
Green without yellow |
Mohs hardness |
8,5 |
Origin |
Kenia, Tanzania |
Processing recommendations* |
|
Ultrasound sensitivity |
Usually none |
Reaction to steam |
Risky |
Reaction to heat |
Changes in temperature can cause cracks |
Chemical reaction |
Hydrofluoric acid |
Tourmaline
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Stone type |
Tourmaline |
Common types of finishing |
Heating |
Birthstone of the month |
October |
Gemstone group |
Tourmaline |
Designation of the best colour in trade |
---------- |
Mohs hardness |
7 - 7,5 |
Origin |
Sri Lanka, Tanzania, USA, Afghanistan, Brazil, Madagascar, Namibia, Kenia, Mozambique, Nigeria, Zambia, Myanmar, Pakistan, India |
Processing recommendations* |
|
Ultrasound sensitivity |
Risky |
Reaction to steam |
Risky |
Reaction to heat |
Can cause color change |
Chemical reaction |
Usually none |
* The recommendation is non-binding advice. The customer is responsible for the correct processing of the products. The content of the recommendation was written with great care. Nevertheless, no guarantee can be given for the correctness of the recommendations in individual cases.