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
SurveysOct 16, 2026
How Inflation, Gas Prices Will Affect Holiday Sales The NRF is expecting holiday sales to increase this year, but consumers and retailers alike are facing Grinch-like headwinds.
CollectionsOct 16, 2026
Christina Puchi’s Earrings Hold the UniverseOur Piece of the Week gathers the planets, represented by a variety of colored gemstones, in a pair of 14-karat yellow gold earrings.
IndependentsOct 16, 2026
Reeds Jewelers Expands, Relocates FlagshipThe New York-based jeweler is moving its Amherst flagship store to a larger location in nearby Snyder.
Brought to you by
Meet Gemology’s Next Generation Microscope: GIA® Gemolite® NXT Professional EditionExperience gemstones with greater precision and comfort than ever before.
MajorsOct 16, 2026
Katy Chen Appointed Executive Vice President of Graff USA Chen, who worked at Cartier and Tiffany & Co., will lead retail sales and operations for the luxury jeweler’s 11 U.S. stores.
Weekly QuizOct 15, 2026
This Week’s QuizTest your jewelry news knowledge by answering these questions.
IndependentsOct 15, 2026
Retailer Hall of Fame 2026: Amy and Elise Greenberg For 40 years, sisters Amy and Elise Greenberg have helmed their 126-year-old family business, leading with appreciation and integrity.
ColumnistsOct 15, 2026
Peter Smith: What Is the Culture REP?It’s a term Smith coined and felt compelled to share following a bad experience with an aborted flight and an unfeeling flight attendant.
Brought to you by
Your Piece Could Be the One Editors Talk AboutSubmit your pieces for a chance to win in this year's competition.
WatchesOct 15, 2026
Stephanie Gottlieb’s New Movado Watches Are Made for Your Wrist StackMovado teamed up with the New York-based fine jewelry designer on a new collection of Movado Museum Velura watches.
SourcingOct 15, 2026
Signet Jewelers, Richemont May Join Bidder for De Beers, Report SaysThe two companies are reportedly in talks to join the Global Diamond Consortium, led by former De Beers CEO Gareth Penny, as per Bloomberg.
CollectionsOct 15, 2026
Wolf x Marla Aaron's New Jewelry Box Is for Some (Not All) of Your ThingsThe “Some of the Things” box follows the two larger “Everything” box designs with the look and function of antique sewing and toolboxes.
IndependentsOct 14, 2026
Retailer Hall of Fame 2026: Coleman and Mitchell ClarkFourth-generation jewelers Coleman and Mitchell Clark exemplify the best qualities of their predecessors: humility, modesty, and confidence.
SourcingOct 14, 2026
Manuel Marcial de Gomar, ‘The Emerald Whisperer,’ Dies at 90The gem hunter, whose 70-year career was defined by adventure and exploration, is remembered for his steadfast faith and sense of wonder.
FinancialsOct 14, 2026
LVMH’s Jewelry Brands Turn in ‘Very Good’ Performance in Q3 Tiffany & Co. continued its full-scale store renovation project while Bulgari’s high jewelry collection generated “record-breaking revenue.”
Events & AwardsOct 14, 2026
Chicago Responsible Jewelry Conference Releases 2026 ProgramThis year’s sessions feature leading voices from human rights, legal, and conservation organizations.
MajorsOct 13, 2026
David Webb Owner Purchases Lugano JewelryThe high-end jewelry retailer was sold to private investment firm Middle West Partners and a group of longtime clients.
IndependentsOct 13, 2026
Retailer Hall of Fame 2026: Sean DunnDunn, this year’s Single-Store Independent inductee, is passionate about innovation and telling the story of natural diamonds.
AuctionsOct 13, 2026
Christie's Geneva To Auction 'Bulgari Pink' DiamondThe 24-carat fancy intense pink diamond ring could fetch up to $18 million at the November sale.
IndependentsOct 13, 2026
Greenwich St. Jewelers’ New Candle Smells Like HomeThe “Island Jewel” candle honors New York City and Puerto Rico and raises money for the island’s water relief efforts.
TechnologyOct 13, 2026
GemFind Is a New JA Member Benefit Partner The partnership will give JA members access to preferred pricing, exclusive benefits, technology solutions, education, and resources.
SurveysOct 09, 2026
These Will Be the 10 Busiest Days for In-Store Shopping This Holiday SeasonStores should expect to see the most customers on Nov. 27, and Christmas week is expected to be hectic too, as Dec. 25 falls on a Friday.
CollectionsOct 09, 2026
Elisa Solomon Collabs With Serendipity 3 on ‘Frozen Hot Chocolate’ CharmThe charm, our Piece of the Week, features brown diamond frozen hot chocolate topped with white diamond whipped cream and a ruby straw.
AuctionsOct 09, 2026
8-Carat Blue Diamond Goes Unsold at UK Jewelry Auction The top lot of Elmwood’s recent fine jewelry sale in London was a 1.84-carat, D color Tiffany & Co. solitaire diamond ring.
WatchesOct 09, 2026
Movado to Sell Majority Stake in Ebel for $66.5MThe watch company agreed to sell a 95 percent interest to a group comprised of F.P. Journe, Chanel, and Swiss watch exec Pierre Jacques.
Policies & IssuesOct 08, 2026
Third Wave of IEEPA Tariff Refunds Begins This round of tariff refunds is for importers that have sued over IEEPA tariffs in the Court of International Trade and won.
CollectionsOct 08, 2026
Brent Neale’s New Collection Goes ‘Back to Basics’It revisits the brand’s most requested silhouettes, from "Pillow"-set necklaces and bracelets to "Signature"-set rings and earrings.
SourcingOct 08, 2026
Ethical Gem Fair Heads Back to BrooklynThe trade-only event includes buying opportunities as well as educational sessions on artisanal mining, the new Paraíba source, and more.
