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.”
Editors' Picks
Sponsored by
More on Lab-Grown
The Latest
SourcingFeb 04, 2025
New Deal With Botswana Is Done, De Beers Confirms The agreement will allocate an increasing proportion of the country’s rough diamonds to the government of Botswana over the next decade.
Events & AwardsFeb 04, 2025
Van Cleef & Arpels’ Astronomy-Inspired Jewelry to Land at AMNH“Cosmic Splendor: Jewelry From the Collections of Van Cleef & Arpels,” opens April 11 at the American Museum of Natural History.
SurveysFeb 04, 2025
Valentine’s Day Jewelry Spending Forecast to Hit Record High, Says NRFThose celebrating Valentine’s Day this year are expected to spend a record $27.5 billion on jewels, flowers, candy, and more.
Brought to you by
3 Ways to Capitalize on America’s Newfound Love of Colored GemsColored stones are stepping into a jewelry spotlight typically reserved for diamonds—are you ready to sell color?
EditorsFeb 03, 2025
Best Jewelry Moments From the 2025 Grammy Awards From Lady Gaga’s 1930s Tiffany & Co. necklace to Taylor Swift’s “T,” Michelle Graff recaps the night’s most memorable jewelry looks.
Weekly QuizJan 30, 2025
This Week’s QuizTest your jewelry news knowledge by answering these questions.
MajorsFeb 03, 2025
Qurate to Close HSN’s Florida HQ Amid RestructuringLayoffs will reportedly start next month as HSN plans to move into QVC’s location in Pennsylvania.
EditorsFeb 03, 2025
Q&A: 5 Jewelry Designers on Shopping the 2025 Tucson Gem ShowsA group of creatives talked to Associate Editor Lauren McLemore about their approach to the annual Tucson gem, mineral, and fossil shows.
Brought to you by
3 New Year’s Resolutions for Jewelry Lovers The new year feels like a clean slate, inspiring reflection, hope, and the motivation to become better versions of ourselves.
AuctionsJan 31, 2025
Elizabeth Taylor’s Diamond Bracelet Outshines Estimate at U.K. AuctionThe auction also featured the sale of a Cartier necklace made when Egyptomania was sweeping Great Britain.
CollectionsJan 31, 2025
Piece of the Week: Lalaounis’ Good Luck Charm for 2025The “Blossom Rosette” blooms with love, beauty, and hope for the year ahead.
IndependentsJan 31, 2025
Harvey Rovinsky, Longtime Owner of Bernie Robbins Jewelers, Dies at 77Rovinsky is remembered as a great mentor who made the employees of his stores feel like family.
Events & AwardsJan 31, 2025
Facets of Fire Has a Diamond Challenge for RetailersFor every jeweler who tries their luck, the company will make a donation to Jewelers for Children.
MajorsJan 30, 2025
WJA Chapter Leaders Resign as Fallout From DEI Remarks SnowballsThe boards of at least five chapters have resigned in response to controversial statements the WJA national board president made last month.
Policies & IssuesJan 30, 2025
RJC Executive Director Melanie Grant Is Stepping Down An experienced jewelry writer and curator, Grant led the organization for two years.
CollectionsJan 30, 2025
Pharrell Williams Brings Tahitian Pearls to His New Tiffany & Co. CollectionFive new designs were added, all donning Tahitian cultured pearls and spear-like trident motifs, along with the new “Titan” setting.
Events & AwardsJan 30, 2025
Registration Open for Converge 2025The inaugural event is being co-hosted by the American Gem Society and the Gemological Institute of America.
MajorsJan 30, 2025
24 Karat Club of New York Elects 5 New MembersJewelers of America’s Annie Doresca and AGTA CEO John W. Ford Sr. are among the new members.
CollectionsJan 29, 2025
Boucheron’s High Jewelry Takes the Form of ‘Untamed Nature’The jeweler’s latest high jewelry collection looks into the Boucheron archives to create a “living encyclopedia of high jewelry.”
FinancialsJan 29, 2025
LVMH Watch, Jewelry Sales End the Year DownWatch and jewelry sales slipped 3 percent in 2024, though the luxury conglomerate did see business pick up in the fourth quarter.
MajorsJan 29, 2025
Chanel Names New General Manager of Watches, Fine Jewelry for USOlivier Kessler-Gay will take over the role on March 3.
SurveysJan 29, 2025
Consumer Confidence Slips for Second Consecutive Month It hit a four-month low in January due to concerns about the job market, though consumers remain bullish about the stock market.
Events & AwardsJan 29, 2025
Chris Ploof To Teach Mokume Gane at AJSThe jewelry designer and master metalsmith will present on the ancient Japanese metalworking technique at the Atlanta Jewelry Show in March.
SourcingJan 28, 2025
WFDB Joins Efforts to Promote Natural Diamonds With New CampaignThe “Moments” social media campaign emphasizes the emotional ties between natural diamonds and life’s special milestones.
CollectionsJan 28, 2025
Bliss Lau Celebrates the Intricate Mosaic of Identity in New CollectionThe versatile “As We Are” collection features 14 pieces with interlocking designs allowing for 27 different looks worn around the body.
SourcingJan 28, 2025
Botswana’s First Olympic Gold Medalist Is Now a De Beers Ambassador Letsile Tebogo will help to promote natural diamonds and the good they have done for his country.
Events & AwardsJan 28, 2025
NouvelleBox Show Returns to New York CityThe showcase, in its second year, will feature more than 20 international brands at its curated event from Feb. 2-4.
Recorded WebinarsJan 28, 2025
Watch: Fine Jewelry Market Predictions for 2025 “My Next Question” guests Sherry Smith and Edahn Golan share their 2025 forecasts, from sales and marketing to what retailers should stock.
