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
CrimeNov 12, 2026
1 of 7 Men Charged in $100M Brinks Heist to Plead GuiltyThree of the other alleged perpetrators will stand trial next March, while two remain on the lam and one was deported late last year.
AuctionsNov 12, 2026
24-Carat ‘Bulgari Pink’ Diamond Sells for $14.8MUnseen for more than seven decades, the fancy intense pink diamond was the star of Christie’s Geneva jewelry auction.
WatchesNov 12, 2026
Zadok Jewelers Now Offers Certified Pre-Owned Rolex WatchesThe curated selection is available online and at its showroom in Austin, Texas.
Brought to you by
DSF Antique Jewelry: Fine Jewelry, Signed Designers, and a World of Rare DiscoveriesWith over 50 years experience in the trade, DSF Antique Jewelry offers quality, craftsmanship, condition, and remarkable variety.
IndependentsNov 12, 2026
Greenberg’s Jewelers Welcomes New Fourth-Generation MembersThe next generation understands what makes the 126-year-old retailer special, said CEO and Co-President Elise Greenberg.
Weekly QuizNov 12, 2026
This Week’s QuizTest your jewelry news knowledge by answering these questions.
SourcingNov 10, 2026
Botswana in Line to Take Controlling Stake in De Beers, President Says If the Global Diamond Consortium emerges as the top bidder for De Beers, Botswana’s stake will double to 30 percent, Duma Boko said Monday.
ColumnistsNov 10, 2026
Who Checks the Facts When AI Writes Your Jewelry Copy?An incorrect AI-generated ad or product description can cost your store valuable consumer trust.
Brought to you by
How Overnight Mountings’ Bridal Builder Makes Custom Engagement Ring Design Easier to SellWith customization becoming more expected in engagement ring shopping, the Bridal Builder makes the process tangible.
Events & AwardsNov 09, 2026
Here Are the 2027 Gem Award NomineesThese nine individuals and brands are up for a Gem Award in the Jewelry Design, Media Excellence, and Retail Innovation categories.
CrimeNov 09, 2026
Jeweler Pistol-Whipped, $900K in Jewelry Stolen During Home Invasion The incident, which happened in Miami-Dade County, serves as a reminder to jewelers of the dangers of selling and storing jewelry at home.
GradingNov 09, 2026
GIA Acquires Thousands of Gem Specimens With ‘Extraordinary’ InclusionsGIA Analytical Microscopist John Koivula curated the collection of 2,665 crystals, gems, and minerals over a 60-year span.
CollectionsNov 09, 2026
Bibi van der Velden’s Alligators Become High JewelryThe “Eclipse” collection, the brand’s first high jewelry line, centers its alligator motif in diamond and spinel jewels.
EditorsNov 06, 2026
The Spectrum Pieces I Can’t Stop Thinking AboutFrom a Betta fish brooch to a “dragon’s trove” of zircon eggs, here are seven pieces that’ve stuck with Associate Editor Lauren McLemore.
TrendsNov 06, 2026
Pat Pruitt’s DragonFly Earrings Take Flight on Election NightGroundbreaking New Mexico Governor-elect Deb Haaland wore the earrings, our Piece of the Week, when she declared victory on Tuesday.
MajorsNov 06, 2026
SNL’s Colin Jost Finds the Perfect Gift in Kay Jewelers’ Holiday AdJost goes on an epic journey, traversing rough seas and encountering a cyclops, to discover the perfect holiday gift.
Supplier BulletinNov 05, 2026
Winning With GCAL 8X®: What’s Working at the CounterSponsored by GCAL by Sarine
SurveysNov 05, 2026
What Retailers Should Know About Holiday Shoppers This YearFrom shrinking budgets to AI elves, here are five takeaways from holiday reports by Bain, Adobe, Mastercard, NRF, and insights from YouGov.
CollectionsNov 05, 2026
Judi Powers, Russell Jones Unleash Joy With New CollaborationThe designers combined their talents for Little Pet Portraits, hand-painted miniatures of our best friends set in a piece of jewelry.
FinancialsNov 05, 2026
Brilliant Earth Continued to Resonate With High-Income Shoppers in Q3Its non-bridal fine jewelry remains the star of the show, recently launching new collections inspired by Elizabeth Taylor and Jane Goodall.
MajorsNov 05, 2026
Ariana Grande Stars In Swarovski’s Holiday Campaign“Joy: The Swarovski Musical” features Ariana Grande as the leading lady in scenes inspired by classic musical montages.
GradingNov 05, 2026
GIA to Offer Next-Day Holiday ServicesThe lab will bring back its complimentary next-day service for some reports starting next week.
CrimeNov 04, 2026
$250K+ in Undeclared Cartier Jewelry Seized at Philadelphia AirportA Pennsylvania woman failed to declare a ring and a bracelet, discarding the boxes and receipts to conceal the purchases, officials said.
FinancialsNov 04, 2026
Pandora’s Q3 Sales Up 7% Amid Focus on DesignNew collections and relevant marketing pushed the company forward, while Pandora’s lab-grown diamond sales continue to lag.
Events & AwardsNov 04, 2026
NYC Jewelry Week 2026 Is the Largest Edition YetThe citywide celebration, slated for Nov. 16-22, is set to host more than 175 events, including live jewelry-making demos.
MajorsNov 04, 2026
Bergdorf Goodman Names New PresidentLanessa Elrod, former president and CEO of Louis Vuitton Americas, has stepped into the role as the retailer celebrates 125 years.
AuctionsNov 03, 2026
Infinity Gauntlet Set With 170+ Carats of Colored Gemstones Up for AuctionA replica of one of the most powerful objects in the Marvel Cinematic Universe, the glove is heading to auction next month in Abu Dhabi.
IndependentsNov 03, 2026
Longtime Jewelry Marketer Arthur Klein Dies at 89Klein, who had his own marketing agency and worked for Gabriel & Co. and Trans American Diamond, is remembered as a kind man.
