Notes:
•This article deals only with single crystals; polycrystals have different uses and, for example, are not used in jewelry.
• We are not including price estimates for these record-breaking synthetic diamonds. Without a public sale, any estimated value would remain purely speculative. If one of these diamonds is ever sold, we will update this article with the actual price.
Natural diamonds owe much of their value to the difficulty of their extraction and the rarity of certain exceptional sizes or colors. Synthetic diamonds, on the other hand, are reproducible: continuous improvement of the processes allows synthetic diamonds to rise to the status of true jewels, rivaling the finest natural creations in weight, purity, and brilliance.
However, this reproducibility does not mean banality, as producing an exceptional synthetic diamond, free of major flaws, remains a technical feat requiring expertise, patience, and massive investment. These crystals are dramatically reshaping the landscape of fine jewelry, offering designers volumes and colors once reserved for a few mythical stones.
The technological rise of single crystals
In the 1950s, synthetic diamonds, weighing only fractions of a carat, were produced using High Pressure High Temperature (HPHT) and were reserved for tooling.
The 1960s and 1970s saw the first rough diamonds of 5 to 10 carats, still unsuitable for jewelry.
It was not until the 2000s that gem-quality cut diamonds of 5 to 10 carats were produced using HPHT or CVD (Chemical Vapor Deposition), which precisely controls crystal growth.
Each record follows a previous one, and here is a necessarily incomplete chronology.
Chronology of records
2015 – 10.02 carats (cut) – New Diamond Technology (Russia)
Rough HPHT: 32.2 carats → Cut: 10.02 carats. Emerald cut, type IIa, VS1 clarity, E color, excellent finish. IGI Hong Kong certified.
Its growth took 300 hours.
Source: JCK Online (archive)
2016 – 10.07 carats (cut) – New Diamond Technology (Russia)
Intense yellow diamond HPHT, SI1, IGI Antwerp.
Source: Jeweller Magazine
2016 – 10.07 carats (cut) – New Diamond Technology (Russia)
HPHT blue diamond, emerald cut, SI1 IGI Antwerp.
Source: Jeweller Magazine
2018 – 15.32 carats (cut) – New Diamond Technology (Russia)
HPHT type IIa, modified brilliant cushion cut, H/I1, metallic inclusions. Examined by GIA Carlsbad.
Source: GIA Gems & Gemology
2018 – 103.5 carats (rough) – New Diamond Technology (Russia)
HPHT, type Ib, growth in just 14 days.
Source: Rough & Polished (archive)
2019 – 20.22 carats (cut) – New Diamond Technology (Russia)
Rough HPHT: 55.94 carats → Cut: 20.22 carats.
Fancy Vivid Orange – Cushion cut, VS2.
Named « Empress Elizabeth » in homage to Tsarina Elizabeth Petrovna.
Source: Rough & Polished
2020 – 46.20 carats (rough) – Shanghai Zhengshi Technology Co. Ltd. (China)
CVD rough: 46.20 carats → Cut: 12.75 carats.
Type IIa, exceptional chemical purity and transparency, F VVS2, triple excellence in cut and finish quality, certified by IGI Hong Kong.
Source: Rapaport
2020 – 115.65 carats (rough) – Meylor Global LLP (United Kingdom)
HPHT rough, examined by IGI.
Source: JCK Online | IGI
2020 – 129.47 carats (rough) – New Diamond Technology (Russia)
Raw HPHT, type Ib (29.5×29.5×21 mm), 400 hours of growth.
Source: Rough & Polished
2021 – 150.42 carats (rough) – Dr. Andrey Katrusha (Alkor-D, Ukraine) / Meylor Global LLP (United Kingdom)
Raw HPHT, opaque blue, type IIb (28.55 x 28.25 x 22.53 mm), produced in Kyiv, examined by IGI.
Sources: Guinness World Record | IGI
2022 – 16.41 carats (cut) – Shanghai Zhengshi Technology Co. Ltd. (China)
CVD, princess cut.
Source: GIA News
2022 – 30.18 carats (cut) – Ethereal Green Diamond, LLP (India)
CVD, emerald cut, H, VS2, certified by IGI.
Named « Pride of India ».
Sources: IGI | Ouros Jewels
2022 – 141.58 carats (rough) – Alkor-D (Ukraine) / Meylor Global LLP (United Kingdom)
Raw HPHT, semi-transparent grey, (28.9 x 28.5 x 20.75 mm), examined by IGI.
Source: JCK Online
2024 – 75.33 carats (cut) – Ethereal Green Diamond, LLP (India)
CVD rough: 190 carats → Cut: 75.33 carats.
(23.01 mm x 22.15 mm x 19.93 mm)
Square-emerald cut, type IIa, VS2, 270 days of growth, certified by IGI.
Named « Celebration of India ».
Sources: IGI | The Times of India
2025 – 156.47 carats (rough) – LiLiang Diamond Co., Ltd. (Henan, China)
Raw HPHT (36.70 mm x 32.85 mm x 15.30 mm), IGI certified.
Source: LiLiang Diamond
There is no doubt this latest record will be broken. Why not by a French laboratory? Gemmes de France is ready to take on the challenge if a potential buyer comes forward!
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