Provides a visual guide to the internal features of natural, synthetic and treated rubies.
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Examines Jaipur’s role as a coloured stone cutting and jewellery manufacturing centre, with profiles of 17 companies and their factory, trading and retail operations.
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Determines whether blue zircon, inadvertently altered to brown by exposure to long-wave UV radiation, can be restored to its original colour through the use of incandescent light.
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A report on the colour treatment process for these intensely greenish yellow to yellowish-green cultured pearls and the techniques for identifying them.
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Amber samples were heat-treated, using various procedures and parameters, in an effort to reproduce materials found in the jewellery market.
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An examination of the gemmological and spectroscopic properties of CVD synthetic diamonds from Gemesis Corp.
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Knowledge of type allows gemmologists to better evaluate if a diamond might be treated or synthetic, and whether it should be sent to a laboratory for testing.
Read MoreModern gemmologists and diamantaires are faced with a broad spectrum of colour and clarity treatments ranging from the simple to the highly sophisticated.
Read MoreThe Diamond Trading Company (DTC) Research Centre had the opportunity to examine a diamond that, on submission to a commercial gem laboratory, turned out to be a coated pink diamond.
Read MoreChameleon diamonds are among the rarest of gem diamonds.
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