CrimeAug 05, 2025
Report: Suspect Arrested in 1992 Murder of Miami JewelerOmar Roy, 72, was arrested in connection with the murder of jeweler Dionisio Carlos Valladares.
GradingOct 19, 2016
GIA Examines 5- and 10-Carat Lab-Grown Diamonds
The laboratory said the 5.19-carat diamond represents a “significant milestone” in CVD diamond growing.
Examined by the GIA’s Hong Kong laboratory, this 5.19-carat CVD synthetic diamond is J-equivalent color and VS2-equivalent clarity. It is one of two lab-grown diamonds discussed in research articles published recently by the lab. (Photo credit: Johnny Leung and Tony Leung, courtesy of GIA)
Carlsbad, Calif.--The Gemological Institute of America recently examined two large lab-grown diamonds submitted to its Hong Kong lab, one of which represents a “significant milestone” in diamond growing.
In a research article authored by Billie “Pui Lai” Law and Wuyi Wang, the GIA said it recently examined a 5.19-carat diamond grown using the chemical vapor deposition process.
The stone, which is J-equivalent color and VS2-equivalent clarity, is the largest CVD-grown diamond examined by the lab to date, and the largest ever reported in the jewelry industry.
Breaking the 5-carat barrier is a “significant milestone” for CVD technology, which has been producing bigger diamonds in recent years, a trend that’s expected to continue.
As the GIA noted, “As diamond growth techniques continue to advance, we expect to see more high-quality samples, both in size and clarity.”
The article also stated that the 5.19-carat diamond was submitted to the lab without proper disclosure.
However, the GIA was able to identify it as a CVD synthetic using its standard screening and testing processes, though the lab noted that black inclusions, which often are contained in synthetic diamonds, were not found in this CVD diamond, meaning it could have been mistaken as a mined diamond if only microscopic examination was used.
The identification of this lab-grown diamond “highlights the importance of using advanced spectroscopic instruments as well as conventional gemological techniques to ensure an accurate identification,” the GIA said.
The second article, authored by Wang and Terry “Ping Yu” Poon, discussed the examination of a 10.08-carat blue diamond grown by St. Petersburg, Russia-based New Diamond Technology. NDT is the same company that grew the 5.03-carat blue diamond examined by the GIA’s New York laboratory earlier this year.
Grown using the high-pressure, high-temperature method and disclosed as a synthetic diamond by NDT, the stone is the largest HPHT-grown diamond recorded to date.
The GIA said the emerald-cut stone has a color grade equivalent to fancy deep blue.
More on Grading
The Latest
CollectionsAug 05, 2025
Mignon Faget Commemorates 20th Anniversary of Hurricane KatrinaThe New Orleans-based brand’s “Beyond Katrina” jewels honor the communities affected by the storm.
ColumnistsAug 05, 2025
The PR Adviser: Affiliate Marketing Is the Cost of CoverageLilian Raji explains why joining an affiliate network is essential for brands seeking placements in U.S. consumer publications.
Brought to you by
Taking the Moment Head On: How Rio Grande Champions the Present & Future of Fine JewelryAs a leading global jewelry supplier, Rio Grande is rapidly expanding and developing new solutions to meet the needs of jewelers worldwide.
Events & AwardsAug 05, 2025
JA Announces Seymour & Evelyn Holtzman Bench Scholarship WinnersThe organization has awarded a total of $42,000 through its scholarship programs this year.
Weekly QuizJul 31, 2025
This Week’s QuizTest your jewelry news knowledge by answering these questions.
Events & AwardsAug 04, 2025
Gem Awards, David Yurman Introduce $50K Grant for Emerging DesignersThe winner of the inaugural David Yurman Gem Awards Grant will be announced live at the 2026 Gem Awards gala.
TrendsAug 04, 2025
Amanda’s Style File: August’s Bright BaublesAs summer winds down, celebrate the sunny disposition of the month’s birthstones: peridot and spinel.
Brought to you by
Investing in the Next Generation of Bench JewelersThe Seymour & Evelyn Holtzman Bench Scholarship from Jewelers of America returns for a second year.
CrimeAug 04, 2025
‘The Watch King’ Assaulted, Robbed in QueensMoshe Haimoff, a social media personality and 47th Street retailer, was robbed of $559,000 worth of jewelry by men in construction outfits.
MajorsAug 04, 2025
Borsheims Welcomes New Assistant Facilities ManagerXavier Dibbrell brings more than a decade of experience to the role.
MajorsAug 01, 2025
Helzberg President Julie Yoakum Moves Over to Signet JewelersThe addition of Yoakum, who will lead Kay and Peoples, was one of three executive appointments Signet announced Thursday.
MajorsAug 01, 2025
Jewelers Mutual Names Mike Alexander as President The insurance company’s previous president and CEO, Scott Murphy, has split his role and will continue as CEO.
SourcingAug 01, 2025
Gemfields’ Auction Revenue Drops 50% in H1The nearly six-month pause of operations at its Kagem emerald mine earlier this year impacted the miner’s first-half results.
CollectionsAug 01, 2025
Piece of the Week: Hernsdorf’s ‘Tears of Aphrodite’ NecklaceThe necklace uses spinel drops to immortalize the moment Aphrodite’s tears mixed with her lover Adonis’ blood after he was fatally wounded.
SourcingJul 31, 2025
De Beers Records $189M First-Half Loss The diamond miner and marketer warned last week that it expected to be in the red after significantly cutting prices in Q2.
Events & AwardsJul 31, 2025
These Are the 2025 CASE Award WinnersJewelers of America’s 35th annual design contest recognized creativity, artistry, style, and excellence.
IndependentsJul 31, 2025
Matthew Tratner Takes Over as CBG President Tratner succeeds Andie Weinman, who will begin stepping back from the buying group’s day-to-day operations.
Policies & IssuesJul 30, 2025
Tariff on India Will Be 25%, Trump Says The president made the announcement via Truth Social Wednesday, adding that India also will face a penalty for its dealings with Russia.
FinancialsJul 30, 2025
Kering's Jewelry Brands Resilient As H1 Sales Slide 16%The luxury titan’s star brand Gucci continued to struggle amid a "tough" environment.
WatchesJul 30, 2025
Peek Inside Zadok Jewelers’ New Rolex Showroom in AustinIts opening marks the completion of the retailer’s new 11,000-square-foot store in the Texas capital.
SurveysJul 30, 2025
Consumer Confidence Ticks Up in JulyRespondents shared concerns about tariffs and commentary on the “Big Beautiful Bill.”
SourcingJul 30, 2025
Rob Bates to Release Latest Book in His ‘Diamond District Mystery’ Series“Making a Killing in Diamonds” tells the story of Mimi Rosen, the disappearance of a scientist, and the murder of lab-grown diamond CEO.
EditorsJul 29, 2025
Out & About: Visiting Tacori’s Design Studio in LASenior Editor Lenore Fedow learned a lot when she took a behind-the-scenes factory tour with the jewelry brand earlier this year.
Events & AwardsJul 29, 2025
Melee The Show Welcomes 15 New DesignersThe first-time exhibitors, set to debut at the New York City show, share a devotion to craftsmanship, storytelling, and material integrity.
SourcingJul 29, 2025
Auctim to Offer 7.3M+ Carats of Rough EmeraldsThe online auction house’s September sale will feature rough Brazilian emeralds of various qualities.
MajorsJul 29, 2025
Alexis Padis Re-Elected AGS Board President She’ll lead an executive committee consisting of President-Elect Bryan Moeller, Mitchell Clark, Bill Farmer, and Larry Rickert.
Policies & IssuesJul 28, 2025
U.S.-EU Come to Agreement on Tariffs Announced Sunday, the deal will set the tax on goods imported into the United States from the European Union at 15 percent.
