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 Post subject: Padparadscha-like fancy sapphires with unstable colours
PostPosted: Wed Feb 28, 2018 4:33 pm 
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New report on Padparadscha-like fancy sapphires with unstable colours. Fancy sapphires recently found in Madagascar showing an unstable colour, shifting from pinkish orange (padparadscha-like) to pink after a fading test. In cases where this tenebrescent shift of colour is only minimal (as we have observed in a few padparadschas from Sri Lanka), it can be neglected and does not need specific attention. Some of this new material from Madagascar, however, has shown a very marked shift of colour from (slightly pinkish) orange to pure pink, which in our opinion requires specific disclosure.
As a consequence, the SSEF is now regularly carrying out fading tests on padparadscha and padparadscha-like sapphires, as we have been doing for many years for yellow sapphires. In both cases, this is carried out with prior consent of the client. We then disclose the stability of colour on our reports in the comments section. A further consequence of these new stones shifting from orange to pure pink, is that we do not call these stones padparadscha, but fancy sapphire, adding in such cases an explanation letter to our report.

Read article (PDF) with further explanations on this issue


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 Post subject: Re: Padparadscha-like fancy sapphires with unstable colours
PostPosted: Wed Feb 28, 2018 5:31 pm 
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I would have thought artificial irradiation to produce unstable yellow tones would have already made this necessary, but I suppose it must not have proved a profitable enough deception?


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