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In this study, the Bangkok laboratory examined five low-quality bead cultured pearls sourced directly from a local pearl factory and characterised their features before and after processing.
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Recently, GIA’s laboratory in New York had the opportunity to examine a fascinating pearl find and hear about an even more fascinating story.
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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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This type of pink pyrope garnet, believed to have been mined in Tanzania, shows a distinct colour-change phenomenon resulting from its unique chemical composition.
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Check out some of the most interesting and unusual diamonds and coloured stones submitted to GIA’s laboratories in 2019.
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GIA researchers analysed more than 90,000 natural pink diamonds to better understand how these rare and beautiful diamonds formed and got their colour.
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Opal’s play-of-colour is a lyrical dance: sometimes a grand jeté of bold, broad flashes of colour or smaller, quicksteps of pinpoint flashes.
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De Beers and Alrosa slashed rough diamond sales after ABN AMRO’s says it will no longer finance rough purchases for goods that can’t be cut profitably.
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De Beers and Alrosa slashed rough diamond sales after ABN AMRO’s says it will no longer finance rough purchases for goods that can’t be cut profitably.
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Decent demand for finished jewellery, but less for loose gems. Plus: Lab-grown diamonds and responsible, sustainable business practices.
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