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Find out about how GIA is addressing industry concerns over undisclosed laboratory-grown and simulated fancy melee being mixed in with natural fancy melee.
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Learn about the differences – and similarities – between natural and laboratory-grown diamonds, and how GIA’s researchers and grading laboratories can tell the difference
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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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A look at the gemmological properties and chemical composition of this light blue to light green to green gem material, which is suitable for cabochon cutting.
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Explores statistical data and defining characteristics of gem-quality CVD synthetic diamonds examined by GIA since 2003.
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Presents the underlying physics and methodology of this analytical technique, which has become an essential tool in identifying treated and synthetic diamonds.
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Learn about Mozambican rubies, including their mining history, characteristics and market demand.
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GIA researchers in New York recently had the opportunity to examine one of the most interesting and unique diamond crystals ever found.
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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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