Over Grading of Blue Fluorescent Diamonds Summary
By Michael Cowing |
Twenty-five years ago GIA published the results of a human experiment in the observation of diamonds with various amounts of ...
Read More Over Grading of Blue Fluorescent Diamonds Revisited
By Michael Cowing |
Nineteen years ago GIA published the results of a human experiment in the observation of diamonds with various amounts of ...
Read More The Overgrading of Blue-Fluorescent Diamonds
By Michael Cowing |
Michael D. Cowing FGA AGA Certified Gem Laboratory email: michaelgem@gmail.com Abstract: Decades after the establishment in the mid-twentieth century of ultraviolet-free ...
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A Place for CZ Masters in Diamond Colour Grading
By Michael Cowing |
Figure 2. Complete set of GIA graded diamond masters from E through M. Over the last 20 years and despite ...
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