1.21 CTS GIA CERTIFIED ALEXANDRITE - COLOUR CHANGE [ALX2]
- SKU
- Dimensioni (mm)
- 7.000 x 5.000 x 4.000mm
- Peso (cts)
- 1.210
- Certificate Gem Lab
- GIA
- Shape
- Oval
- Tipo
- Faceted
- Colori
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ALEXANDRITE
This is a natural untreated Alexandrite that was mined in the late 1990s and the miner has now decided to release them-this was from the top producing mine in Tanzania which is now close-the certificate was just recently done.
Weight 1.21 cts
Size: 7.1 x 5.39 x 3.94mm
The magic of changing colours
The most sensational feature about this stone, however, is its surprising ability to change its colour. Green or bluish-green in daylight, alexandrite turns a soft shade of red, purplish-red or raspberry red in incandescent light. This unique optical characteristic makes it one of the most valuable gemstones of all, especially in fine qualities.
Alexandrite is very scarce: this is due to its chemical composition. It is basically a chrysoberyl, a mineral consisting of colourless or yellow transparent chrysoberyl, chrysoberyl cat’s eye and colour-changing alexandrite (also in cat’s eye varieties). It differs from other chrysoberyls in that it not only contains iron and titanium, but also chromium as a major impurity. And it is this very element which accounts for the spectacular colour change. Rarely, vanadium may also play a part. According to CIBJO nomenclature, only chrysoberyls displaying a distinct change of colour may be termed alexandrite.
Like many other gemstones, alexandrite emerged millions of years ago in a metamorphic environment. But unlike many others, its formation required specific geological conditions. The chemical elements beryllium (a major constituent in chrysoberyl) and chromium (the colouring agent in alexandrite) have contrasting chemical characteristics and do not as a rule occur together, usually being found in contrasting rock types. Not only has Nature brought these contrasting rock types into contact with each other, but a lack of the chemical element silica (the second most common element in the Earth’s crust) is also required to prevent the growth of emerald. This geological scenario has occurred only rarely in the Earth’s history and, as a result, alexandrite crystals are very scarce indeed.
- SKU
- Dimensioni (mm)
- 7.000 x 5.000 x 4.000 mm
- Peso (cts)
- 1.210
- Certificate Gem Lab
- GIA
- Shape
- Oval
- Tipo
- Faceted
- Colori
-
ALEXANDRITE
This is a natural untreated Alexandrite that was mined in the late 1990s and the miner has now decided to release them-this was from the top producing mine in Tanzania which is now close-the certificate was just recently done.
Weight 1.21 cts
Size: 7.1 x 5.39 x 3.94mm
The magic of changing colours
The most sensational feature about this stone, however, is its surprising ability to change its colour. Green or bluish-green in daylight, alexandrite turns a soft shade of red, purplish-red or raspberry red in incandescent light. This unique optical characteristic makes it one of the most valuable gemstones of all, especially in fine qualities.
Alexandrite is very scarce: this is due to its chemical composition. It is basically a chrysoberyl, a mineral consisting of colourless or yellow transparent chrysoberyl, chrysoberyl cat’s eye and colour-changing alexandrite (also in cat’s eye varieties). It differs from other chrysoberyls in that it not only contains iron and titanium, but also chromium as a major impurity. And it is this very element which accounts for the spectacular colour change. Rarely, vanadium may also play a part. According to CIBJO nomenclature, only chrysoberyls displaying a distinct change of colour may be termed alexandrite.
Like many other gemstones, alexandrite emerged millions of years ago in a metamorphic environment. But unlike many others, its formation required specific geological conditions. The chemical elements beryllium (a major constituent in chrysoberyl) and chromium (the colouring agent in alexandrite) have contrasting chemical characteristics and do not as a rule occur together, usually being found in contrasting rock types. Not only has Nature brought these contrasting rock types into contact with each other, but a lack of the chemical element silica (the second most common element in the Earth’s crust) is also required to prevent the growth of emerald. This geological scenario has occurred only rarely in the Earth’s history and, as a result, alexandrite crystals are very scarce indeed.
Fornitore di spedizioni | Spedizione a Australia | Spedizione nel resto del mondo |
---|---|---|
FedEx | $12.00 / 3 giorni | $39.00 / 10 giorni |
Australia
FedEx è scontato a $12.00 sugli ordini con 2 o più articoli
Resto del mondo
FedEx è scontato a $39.00 sugli ordini con 2 o più articoli
|
||
Registered Shipping | $9.00 / 7 giorni | $16.00 / 21 giorni |
Australia
Registered Shipping è scontato a $9.00 sugli ordini con 2 o più articoli
Resto del mondo
Registered Shipping è scontato a $16.00 sugli ordini con 2 o più articoli
|
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Positivo
Good stone great service
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Positivo
Great thank very much, lovely pearls.
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Positivo
Nice piece of rough. thankyou
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Positivo
Nice stone. Thankyou
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Positivo
Have received the rough. Nice colour. Thankyou
Verifica
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Descrizione Preciso
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Immagini accurate
Comments
The Verified Seller responsible for this item has diligently provided us with accurate and comprehensive information, encompassing crucial details such as weight, dimensions, and treatment. It is important to reiterate our commitment to upholding the highest standards of integrity and transparency in the gemstone industry. As part of our policy, we strictly permit the sale of exclusively natural gemstones that have been sourced directly from the Earth. However, in the event that a gemstone has undergone any form of treatment, it is mandatory for the seller to provide full disclosure regarding the treatment process. Furthermore, we would like to emphasize that man-made gemstones, including simulants and imitations, are strictly prohibited on our platform. We prioritize the promotion of authentic, natural gemstones to ensure a genuine and trustworthy marketplace for our valued customers. Should you have any further inquiries or require additional assistance, please do not hesitate to reach out. We are here to assist you and provide a seamless experience on Gem Rock Auctions.