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GradingFeb 24, 2016
5-Carat Lab-Grown Blue Diamond Graded by GIA
It’s the largest faceted lab-grown blue the Gemological Institute of America’s ever studied, and it received a color grade of fancy deep.
The GIA examined this 5.03-carat fancy deep blue high-pressure, high-temperature (HPHT) lab-grown diamond. (Photo credit: Sood (Oil) Judy Chia)
New York--The Gemological Institute of America’s New York laboratory recently evaluated the largest lab-grown blue diamond it’s seen to date, a 5.03-carat stone made by a diamond company based in St. Petersburg, Russia.
According to a Lab Note authored by GIA researchers Kyaw Soe Moe, Paul Johnson, Ulrika D’Haenens-Johansson and Wuyi Wang, the emerald-cut diamond was produced by NDT.
NDT, or New Diamond Technology, is one of the founding members of the new International Grown Diamond Association. It’s also the company that produced the world’s largest known colorless diamond, a 10.02-carat, F color, VS1 stone cut from a 32.26-carat piece of rough and submitted to IGI Hong Kong last year.
The Lab Note stated that the 5.03-carat diamond exhibited a number of traits characteristic of diamonds grown using the high-pressure, high-temperature (HPHT) process, including color zoning and a cuboctahedral growth pattern.
The GIA researchers graded the stone a VS1, fancy deep blue. They noted that this is a very attractive hue that contains no other color component, a rarity among natural type IIb diamonds.
The evaluation of a lab-grown blue diamond of this size was so significant that the GIA researchers opted to have the Lab Note published online in advance of the next edition of Gems & Gemology, the GIA’s quarterly journal.
To read the complete article on the 5.03-carat fancy deep blue lab-grown diamond, go to GIA.edu.
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