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    About

    Clive Washington

    Senior Lecturer, University of Nottingham, U.K.

    Articles by


    Clive Washington

    Gemstone Radiation Treatment

    Gemstone radiation is a common but little understood technique for altering gem colors. Learn how it works and what gems usually receive this treatment.…

    Lap Testing

    An overview on lap testing and the results of test. In an attempt to improve faceting, various laps and polishing combinations were performed and…

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