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IGI Grades Guinness World Record Lab-Grown Diamond

Institute analyzes historic 109.58 and 115.65 carat diamonds

Antwerp, Belgium (October 1, 2020) — The International Gemological Institute (IGI) recently had the honor to grade and analyze the Guinness World Record Holder for the largest black lab-grown diamond in history. Grown by Meylor Global, which also produced the world’s largest polished HPHT lab-grown diamond, this stone is a milestone of innovation in the industry.

“We are pleased that Meylor Global entrusted IGI to grade this landmark diamond,” said IGI CEO Roland Lorie. “The Institute pioneered lab-grown diamond certification back in 2005 and for the past 15 years, we have continuously prided ourselves in taking part of monumental moments such as this, which support the development of lab-grown diamonds.”

In September, IGI received two large HPHT-produced lab-grown diamonds from Meylor Global, weighing in at 109.58 and 115.65 carats respectively. The Institute analyzed the two crystals under visible spectroscopy and FTIR mid-infrared spectroscopy that showed neither were subject to color enhancement and both were boron containing Type llb (2b) diamond types.

Additionally, both diamonds were subjected to standard long wave (366 nm) and short wave (254 nm) ultraviolet light and were found to be inert; however, the 115.65 carat diamond showed an orange reaction in long wave ultraviolet light. Overall, when they were exposed to high energy short wave ultraviolet light, they exhibited the standard reaction of HPHT grown diamonds – very strong fluorescence and phosphorescence.

“The significant milestone of 100ct+ size in diamond size was achieved by our company in a very short time and the next even more promising target of 200 ct+ is right now under deep scientific investigation,” previewed Meylor Global CEO Yuliya Kusher.

For more information on this record-breaking diamond, please visit

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About IGI

The International Gemological Institute (IGI) operates 18 laboratory locations around the world grading finished jewelry, natural diamonds, lab-grown diamonds and gemstones – and 14 schools of gemology graduating thousands of new jewelry professionals annually. For over 45 years, IGI has provided the fine jewelry community and consumers with a broad range of services including independent diamond grading reports, colored stone reports, identification and appraisal reports, diamond authentication and attestation of origin, laser inscription services, as well as the issuing of the traditional jewelry identification report. Regardless of location or marketplace, an authentic IGI Laboratory Report is the common language of trust and confidence in the gemological world.

About Meylor Global

Meylor Global is an international supplier of lab grown diamonds. Produced using the HPHT process, which replicates and accelerates natural growth, their inventory includes weights from 0.01 to 20.00 carats, offered in a broad range of colorless and fancy-colored options. All Meylor Global lab-grown diamonds are graded to the same specifications as natural diamonds and accompanied by Diamond Grading Reports from leading independent laboratories. You can learn more on Facebook, Instagram or the company website.

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