Earlier this month IGI received two large HPHT-produced lab-grown diamonds for analysis and grading. One of those stones has become the Guinness World Record Holder for the largest black lab grown diamond in history.
Grown by Meylor Global, who also produced the world’s largest polished HPHT lab-grown diamond, these historic black Type IIb rough crystals weighed in at 109.58 carats (25.33mm x 24.67mm x 19.82 mm) and 115.65 carats (29.40mm x 27.90mm x 23.44mm) respectively.
World’s Largest Black Diamonds Project
In addition to gem-quality lab-grown diamonds, the company produces diamond plates, anvils and lenses used in optic, electronic, mechanical and quantum applications. We asked Meylor Global CEO Yuliya Kusher to describe the project which resulted in these record-setting black crystals.
The two record diamond stones were grown consequently within the frameworks of the “World’s Largest Black Diamonds Project” initiated at our company in the beginning of the year 2020. The innovative approach in physical chemistry of diamond growth combined with sophisticated technological methods and advanced high pressure equipment allowed us to obtain record-breaking extra large diamond single crystals, having in mind the idea of getting the biggest possible diamond plate in the one-inch plus size (25 x 25mm).
The semiconducting properties of our large type IIb diamond stones, specifically intended to produce the single sector diamond plates ((111) or 100) orientations, will greatly facilitate the development of diamond based electronics by boosting the related research with CVD methods diamond layers overgrowth.
Spectroscopical analysis
IGI analysis under visible spectroscopy and FTIR mid-infrared spectroscopy showed the two crystals were not subject to color enhancement and are the boron containing Type IIb (2b) diamond type.
Ultraviolet analysis
Both crystals were subjected to standard long wave (366 nm) and short wave (254) ultraviolet light and found to be inert.
However, the seed crystal of the 115 carat stone showed an orange reaction in long wave ultraviolet light.
When exposed to high energy short wave ultraviolet light, they exhibited the standard reaction of HPHT grown diamonds. Very strong fluorescence (left) and phosphorescence (right).
More to come
According to Kusher, this record-setting achievement is just a step toward another goal.
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.
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.