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Corundum Treatment: Punsiri Technique

Approximately a year ago, unusual sapphires with "colorless rims" – especially when viewed submersed in methylene iodide – began to appear in the trade. The treatment raised speculation these might be subjected to a hitherto unknown lattice diffusion technique. Months later, the American Gem Trade Association's Gem Trade Laboratory noted it had not discovered any form of lattice diffusion in the sapphires, but concluded the stones showed diagnostic characteristics of heat treatment. 

Read more: Corundum Treatment: Punsiri Technique

Sapphires from Australia

Australian Sapphire (Australia)

Some of the finest Sapphires in the world herald from this sunburnt country.

Top quality Australian Sapphires exhibit brilliant cornflower blues usually associated with those from Ceylon (Sri Lanka).

Sapphires have been mined in Australia for over 100 years.

The bulk of Australia's Sapphires come from three fields, the Anakie fields in Central Queensland Lava Plains in Northern Queensland, and the New England fields around Inverell in the north east of New South Wales.

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Corundum Treatment: Beryllium Diffusion of Rubies and Sapphires

Beryllium-Diffused Blue Sapphire

"The addition of beryllium will not produce a blue colour in corundum. However, as the research of Dr. John Emmett and others has shown, a blue sapphire with a concentration of titanium higher than the combined concentration of magnesium that is inherent in the stone and the beryllium that is introduced may remain blue after beryllium diffusion," said Christopher Smith. "With this knowledge in hand, to date there are three potential reasons why beryllium could be encountered in blue sapphires. One relates to the original time when they were treating these stones to produce padparadscha colours. During a standard run when treating a large number of samples, a certain number of those stones remained light blue because of the inherent chemical composition and the amount of beryllium that entered the lattice. As time passed, another option includes inadvertent contamination," which could occur if blue sapphires were heated using standard techniques in the same furnaces used for beryllium diffusion, without changing the internal components. "Another is that beryllium could be intentionally added to lighten a darker stone. In some of the information we have collected, at least in part, beryllium diffusion is being done intentionally to try to lighten stones that are over-coloured or dark."

Read more: Corundum Treatment: Beryllium Diffusion of Rubies and Sapphires

Contemporary Kashmir Sapphire Inclusions

Many stones have been certified "Kashmir" by the major laboratories and others were in the rough with distinctive kaolin matrix. This newer material shares many old Kashmir "gem" inclusions although the bulk of material has been commercial quality. A variety of inclusions are photographed below with caption when you click on the photograph.

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Padparadscha Sapphire

Padparadscha Sapphire

Padparadscha is easily one of the most abused gem names. Ceylonese dealers use it as a catch-all term for any sapphire that can't be considered a ruby.

Because the jewellery industry has not yet adopted any standardised colour measurement system, there is no way to precisely quantify the amount of orange and pink, plus their tonal strength, that constitutes padparadscha colour.

Read more: Padparadscha Sapphire

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The Geohavens name is an assurance of timeless beauty, distinct quality and uncompromising value. The Company spares no effort in sourcing from the farthest markets and the deepest mines in order to unearth the most attractive gems.

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