EditorsDec 13, 2021
Out & About: Watching De Beers Grow Diamonds in OregonLab-GrownFeb 02, 2022
GIA Examines Largest Known Diamond Grown Using CVD
It is more than 16 carats and G color/VVS2 clarity as grown, which is unusual in CVD diamonds.
This 16.41-carat princess-cut diamond produced using the CVD process measures 13.97 × 13.87 × 9.56 mm. Recently examined and graded by GIA, it is G color and VVS2 clarity. (Photo credit: Towfiq Ahmed)
Carlsbad, Calif.—Scientists at the Gemological Institute of America recently examined what is believed to be the largest diamond grown using the chemical-vapor deposition process, breaking a record set just last year.
The lab said Tuesday that the diamond is a 16.41-carat princess-cut stone grown by Shanghai Zhengshi Technology Co. Ltd.
The diamond had the “observable characteristics” of diamonds grown using the CVD process, including strong graining throughout—common in CVD stones—that gives the diamond a “wavy” appearance, as visible in the video below.
The lab said Tuesday that the diamond is a 16.41-carat princess-cut stone grown by Shanghai Zhengshi Technology Co. Ltd.
The diamond had the “observable characteristics” of diamonds grown using the CVD process, including strong graining throughout—common in CVD stones—that gives the diamond a “wavy” appearance, as visible in the video below.
The 16.41-carat lab-grown diamond is exceptional for another reason in addition to its size.
The diamond is G color and VVS2 clarity. GIA confirmed through detailed spectroscopic readings it was not treated post-growth to improve its color, which is unusual.
GIA Vice President of Research and Development Dr. Wuyi Wang, who examined the diamond, noted, “We have seen very few CVD diamonds of this quality.”
The 16.41-carat stone breaks the previous record for largest CVD diamond—a 14.60-carat emerald-cut stone produced in India and reported on by the International Gemological Institute in August 2021—by nearly two carats.
And it tops the record-holder before that, a 12.75-carat round brilliant lab-grown diamond, by almost four carats.
In article on the 16.41-carat lab-grown diamond authored by Wang and GIA research associates Stephanie Persaud and Elina Myagkay, the authors noted how the technology behind both CVD and high-pressure, high-temperature growth processes for diamonds has advanced significantly in the last two decades.
Wang noted in a GIA news release that he first examined a CVD diamond back in 2003, and it was less than half a carat, pear shaped and brown.
“This 16.41-carat laboratory-grown diamond demonstrates the advances in CVD growth technology. This achievement has important implications for the many scientific and industrial applications for high-quality laboratory-grown diamonds,” he said.
The article is available on the GIA’s website. It also will be published in an upcoming issue of Gems & Gemology, GIA’s quarterly research journal.
Related stories will be right here …
The diamond is G color and VVS2 clarity. GIA confirmed through detailed spectroscopic readings it was not treated post-growth to improve its color, which is unusual.
GIA Vice President of Research and Development Dr. Wuyi Wang, who examined the diamond, noted, “We have seen very few CVD diamonds of this quality.”
The 16.41-carat stone breaks the previous record for largest CVD diamond—a 14.60-carat emerald-cut stone produced in India and reported on by the International Gemological Institute in August 2021—by nearly two carats.
And it tops the record-holder before that, a 12.75-carat round brilliant lab-grown diamond, by almost four carats.
In article on the 16.41-carat lab-grown diamond authored by Wang and GIA research associates Stephanie Persaud and Elina Myagkay, the authors noted how the technology behind both CVD and high-pressure, high-temperature growth processes for diamonds has advanced significantly in the last two decades.
Wang noted in a GIA news release that he first examined a CVD diamond back in 2003, and it was less than half a carat, pear shaped and brown.
“This 16.41-carat laboratory-grown diamond demonstrates the advances in CVD growth technology. This achievement has important implications for the many scientific and industrial applications for high-quality laboratory-grown diamonds,” he said.
The article is available on the GIA’s website. It also will be published in an upcoming issue of Gems & Gemology, GIA’s quarterly research journal.
Another lab-grown diamond record was set recently, this one for a rough stone that was examined by IGI.
The lab said Jan. 20 that it recently analyzed a 150.42-carat blue diamond grown by biotech company Meylor Global using the HPHT method.
It is the heaviest rough lab-grown diamond on record, breaking the previous benchmark of 115 carats, also set by Meylor Global in September 2020.
The record for a faceted and colorless/near-colorless HPHT-grown diamond is 15.32 carats, tested by GIA in 2018.
The 150-carat diamond is gem-quality, IGI and Meylor confirmed, but Meylor hasn’t decided what it will do with the diamond.
IGI also noted that it recently examined another large lab-grown diamond from Meylor, this one a gray diamond weighing 141.58 carats.
Pictured at right is the 150.42-carat lab-grown rough diamond produced by Meylor Global, while the 141.58-carat stone is pictured at right.
Like GIA, IGI noted that the technology used to grow diamonds continues to improve.
“The acceleration of technology in the lab-grown diamond sector is significant,” said John Pollard, IGI’s recently appointed director of education.
“In addition to record-setting weights, they’re type IIb crystals, a semiconducting category associated with diamond-based electronics. At IGI, we’re seeing new benchmarks from the world’s most advanced producers in jewelry applications and beyond.”
More on Lab-Grown
The Latest
CollectionsOct 10, 2025
Count Down to the Holidays With Astrid & Miyu’s Advent CalendarsThe trio of Advent calendars include a version with 18-karat gold and lab-grown diamond jewelry in a red lacquer jewelry box.
CollectionsOct 10, 2025
Piece of the Week: Marla Aaron’s ‘Nymphenburg Lock’Created in collaboration with Nymphenburg Porcelain, the lock is part of a four-piece collection that took two years to bring to fruition.
MajorsOct 10, 2025
Frederick Goldman Names New VP of SalesJewelry industry veteran Alisa Bunger has taken on the role.
Brought to you by
Protect Your Customers and Your BusinessYou deserve to know what you are selling–to protect your customers as well as your business and your reputation.
SourcingOct 09, 2025
Feriel Zerouki Is Leaving De Beers The company and industry leader’s two-decade tenure with De Beers will come to a close at the end of the month.
Weekly QuizOct 09, 2025
This Week’s QuizTest your jewelry news knowledge by answering these questions.
AuctionsOct 09, 2025
This Fabergé Egg Could Crack $27M At Auction“The Winter Egg” set the world auction record for a Fabergé piece twice at previous Christie’s sales.
MajorsOct 09, 2025
Sy Kessler Buying Watch Batteries as Silver Hits Record High The company will pay 1.5x silver’s current spot price for each pound of silver oxide batteries submitted.
Brought to you by
JA New York Fall Is Right Around the CornerThe upcoming show provides savvy retailers with the opportunity to stock their cases with best sellers in advance of the holiday season.
CollectionsOct 09, 2025
Katkim Launches First Men’s CollectionThe line includes a “Shadow” series crafted exclusively for the new men’s offering and reimagined styles from the brand’s core collections.
SourcingOct 09, 2025
Gemfields’ Mini Mixed-Quality Ruby Auction Garners $11MThe rough on offer was recovered from a newer area at the Montepuez mine.
SourcingOct 08, 2025
In ‘Storied Diamond,’ Jared Jewelers Is Emphasizing the Journey The retailer’s new collection of engagement rings and fashion jewelry is set with natural diamonds that are traceable via blockchain.
CollectionsOct 08, 2025
Emily P. Wheeler Shifts Into Neutral for Latest ‘Ombré’ CollectionThe champagne colorway in her newest “Ombré” collection combines white and trendy brown diamonds, a departure from her usual vibrant hues.
CollectionsOct 08, 2025
Tsuba Designs Inspire Monica Rich Kosann’s New CharmsKosann partnered with the Museum of Fine Arts, Boston, to create a set of necklaces inspired by the artwork on samurai sword handguards.
CrimeOct 07, 2025
Men Who Posed as Utility Workers Found Guilty in Jeweler’s MurderCarlos Jose Hernandez and Joshua Zuazo face life in prison for the October 2024 murder of 72-year-old Detroit-area jeweler Hussein Murray.
CollectionsOct 07, 2025
Jessica McCormack Looks to Sea Spirits for ‘Tempest’ CollectionThe brand’s first high jewelry collection, “Tempest” plays with movement while calling to mind the folklore of the sea.
SourcingOct 07, 2025
Columbia Gem House Announces ‘Opals for Outback Heroes’ FundraiserProceeds from its jewelry raffle will go to a volunteer-run fire and rescue group in the Lightning Ridge area of New South Wales, Australia.
MajorsOct 07, 2025
Stuller Names Its S.E.R.V.E Stars for 2025Stuller said the recipients embody the company’s core values, which include community participation and personal and professional growth.
WatchesOct 06, 2025
This Fall, Citizen’s Forecast Calls for RainCitizen’s new “Rainell” women’s watch has a raindrop-shaped case and is available with a silver-, gold-, purple-, or green-colored dial.
AuctionsOct 06, 2025
The ‘Rolex That Made Rolex’ Heads to Auction at Sotheby’s The “Mercedes Gleitze Rolex Oyster,” named for the British endurance swimmer who made it famous, will go up for sale next month.
GradingOct 06, 2025
GIA India Names Former De Beers Exec as New Managing DirectorAmit Pratihari was previously the managing director of De Beers India and Forevermark India.
SourcingOct 06, 2025
SoCal 24 Karat Club Integrates Into Diamond Club West CoastMembers of the Jewelers 24 Karat Club of Southern California will gain access to expanded services, resources, and connections, DCWC said.
TrendsOct 03, 2025
Selena Gomez, Benny Blanco Tie the Knot Wearing Diamonds, White MetalsGomez’s jewelry included Tiffany & Co. drop-style earrings while Blanco stacked diamonds from Jacob & Co. on his wrist.
GradingOct 03, 2025
Grading Lab HRD Antwerp Names New CEODiamond industry banking veteran Paul De Wachter will take on the role in January 2026.
TrendsOct 03, 2025
Piece of the Week: Kallati’s Pink Sapphire RingTaylor Swift flaunts an Elizabeth Taylor-esque gemstone in promo for her new album, “The Life of a Showgirl.”
CollectionsOct 02, 2025
Boucheron Debuts Cuffs Crafted With 3D-Printed SandIts “Quantre Sand” capsule was made using a 3D sand printing technique borrowed from the automotive and aeronautics industries.
CrimeOct 02, 2025
$1M in Jewelry Stolen in Northern California Smash and Grab Four individuals have been charged in the “takeover-style” robbery of Heller Jewelers last month, and additional charges are expected.
MajorsOct 02, 2025
Neil Lane Jewelry Exhibition Coming to Toledo Museum of Art“Radiance and Reverie” will showcase more than 150 jewels from Lane’s personal collection by Tiffany & Co., Cartier, and more.
