PodcastsSep 16, 2026
Episode 9: Remembering Cindy EdelsteinTwo special guests join the podcast to commemorate the 10th anniversary of the designer advocate, mentor, and author’s untimely passing.
GradingMay 03, 2017
GIA Sees Blue Diamond That’s Synthetic-Natural Composite
The 0.33-carat stone has a very thin layer of CVD-grown Type IIb diamond on top that earned it a grade of fancy blue.
This is the 0.33-carat fancy blue diamond that the Gemological Institution of America determined was a synthetic-natural composite. When asked about the color of the diamond--which does not appear to be all that blue--the GIA said pale colors are difficult to photograph. (Photo by Sood Oil (Judy) Chia.)
New York--The Gemological Institute of America reports that a mined white diamond with an extremely thin layer of blue lab-grown diamond on top was submitted to its New York laboratory recently.
According to an article published online now and slated for the summer print edition of “Gems & Gemology,” the 0.33-carat stone is a composite of CVD synthetic Type IIb diamond overgrowth on a natural Type Ia.
The lab-grown diamond layer is only 80 microns (0.003 inches) thick, but it’s enough for the diamond to grade as a fancy blue.
Though the GIA said the stone was not submitted as a lab-grown diamond, there were a few things that tipped off researchers.
As the article states, the diamond had both nitrogen and boron defects. Nitrogen defects are the most common defect found in natural diamonds, while boron is the element that gives diamonds a blue tint and is a rare impurity, which is why natural blue diamonds are so few and so valuable.
The GIA said it is “very unusual” to see these two elements together in a single diamond, as essentially what they were looking at was a mixed Type Ia and Type IIb diamond. The last time the GIA reported on one of these being found in nature was nearly 10 years ago, in the spring 2009 edition of “Gems & Gemology.”
Secondly, a detailed analysis conducted using the DiamondView machine showed a yellowish-green fluorescence zone at the top of the crown that had a clearly defined boundary visible along the interface layer on the crown facets.
This, combined with SiV- defects and phosphorescence, indicated to GIA researchers that the top layer was a diamond grown using the chemical vapor deposition (CVD) process.
The bottom of the stone, meanwhile, displayed blue fluorescence but no phosphorescence in the DiamondView and had a strain pattern in the pavilion, both of which are consistent with a stone that is a natural Type Ia diamond.
This is the not the first diamond that’s a synthetic-natural combination.
The GIA noted in its research article that CVD diamond films have been applied to natural diamonds since the 1960s, and the successful addition of CVD-grown diamond layers on top of mined diamonds happened in 1993.
But this is the first synthetic overgrowth on a natural diamond with a fancy color grade that the GIA said it has ever seen.
As the lab put it
Editors' Picks
Sponsored by
in an email to National Jeweler on Tuesday: “Although CVD has been experimentally used to grow over natural diamond, it is not a simple process to perform with a favorable result on a gem-quality diamond.”
That is, apparently, until now.
GIA Director of Research and Development Wuyi Wang, along with New York-based GIA researchers Kyaw Soe Moe, Paul Johnson and Ulrika D’Haenens-Johansson, authored the article.
That is, apparently, until now.
GIA Director of Research and Development Wuyi Wang, along with New York-based GIA researchers Kyaw Soe Moe, Paul Johnson and Ulrika D’Haenens-Johansson, authored the article.
More on Grading
The Latest
CollectionsSep 16, 2026
Jessica McCormack, L’Objet Collab on Homewares CollectionMcCormack brings sea-inspired motifs from her “Beaches” collection to L’Objet’s tableware, vanity pieces, and first-ever cutlery set.
CrimeSep 16, 2026
JSA Issues Warning to NJ Jewelers After Rash of Smash and GrabsNine New Jersey jewelers have been victims of smash-and-grab robberies this year, prompting JSA to circulate a list of recommendations.
Brought to you by
Meet Gemology’s Next Generation Microscope: GIA® Gemolite® NXT Professional EditionExperience gemstones with greater precision and comfort than ever before.
IndependentsSep 16, 2026
Bromberg & Co. Names New PresidentMarlin “Brian” Hood, who has been with the store for 20 years, will succeed Ricky Bromberg, who died earlier this month.
Weekly QuizSep 10, 2026
This Week’s QuizTest your jewelry news knowledge by answering these questions.
MajorsSep 16, 2026
Midas Chain Releases ‘House of Midas’ Bridal CatalogThe new bridal catalog features the latest jewelry collections and designs from timeless classics to modern silhouettes.
EditorsSep 15, 2026
2026 Emmys Jewelry: An Either/Or Proposition Stars wore either a necklace or earrings at 78th Primetime Emmy Awards but rarely both, Natalie Francisco notes.
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.
ColumnistsSep 15, 2026
The Levels Your Website Must Clear Before AI Recommends YouJennifer Shaheen compares this new era of AI-powered SEO to a video game: your website must clear one level before advancing to the next.
IndependentsSep 15, 2026
Armadani Launches Retail Support Program for Holiday SeasonThe program highlights “Made in Italy” fine jewelry with digital merchandising, sales education, and local marketing support.
EditorsSep 15, 2026
Q&A: Signet Jewelers’ Joan Hilson on Diamond Demand, the HolidaysHilson, Signet’s chief operating and financial officer, discussed Q2, resurgent natural diamond demand, and why Blue Nile is a standout.
ColumnistsSep 14, 2026
Sherry Smith: Stop Waiting for December to Save Your ChristmasThe stores that have a great December are the ones that made good decisions in August, September, and October, Sherry Smith writes.
AuctionsSep 14, 2026
22 Carats of ‘Sunshine’ Are Up for AuctionThe 22.09-carat fancy yellow “Pragnell Kimberley Sunshine Diamond” is part of the fall jewelry sale at Heritage Auctions.
IndependentsSep 14, 2026
Greenwich St. Jewelers to Unveil Photography Exhibition“Adornos: Jewelry, Memory & What We Pass Down” honors the jewelry’s importance to New York City’s Latine communities.
SourcingSep 14, 2026
Gemfields Sells All Lots at First Emerald Auction in 9 MonthsThe company’s managing director of sales said the results demonstrate “continued strong demand for commercial-quality emeralds.”
SourcingSep 14, 2026
Diamonds Do Good Pledges Support for Eye Care ProgramThe nonprofit awarded a grant to the Gift of Sight initiative spearheaded by South African musician Black Coffee.
CollectionsSep 11, 2026
A Sapphire ‘Stardust’ Ring From Greenwich St. Jewelers The Latine-owned New York jeweler is marking two milestones this year: its 50th anniversary and the 25th anniversary of the 9/11 attacks.
MajorsSep 11, 2026
The Wishing Place by JTV OpensThe jewelry retail broadcast network has sponsored a new space for Make-A-Wish East Tennessee on its campus in Knoxville.
Events & AwardsSep 11, 2026
The Edge Awards Scholarships to 2 Young Jewelry ProfessionalsThe recipients were recognized at the 24 Karat Club of the Southeastern United States’ annual banquet.
MajorsSep 10, 2026
Lagos Founder Steven Lagos Steps Down as CEO Keith Rolfe, CFO and COO of Lagos, is now at the jewelry brand’s helm while Steven takes on the role of executive chairman.
CrimeSep 10, 2026
FBI Offers $50K Reward for ‘Most Wanted’ Fugitive in $1M Jewelry HeistAlberto Perez-Elias is one of four men charged in the armed robbery of a Cape Coral, Florida, jewelry store and remains at large.
AuctionsSep 10, 2026
Massive Matched Pair of Paraíba Tourmalines Head to Sotheby’sThe “Kat Florence Luminas” will be offered together as one lot and could fetch up to $637,000.
SourcingSep 10, 2026
AGTA Announces 4 Newly Elected DirectorsFour directors were elected to the AGTA board and will serve three-year terms beginning in February.
AuctionsSep 10, 2026
Former Sotheby’s, Christie’s Exec Appointed CEO of Julien’s Auctions Ken Citron joins the celebrity memorabilia-focused auction house ahead of its first week-long series of events in Abu Dhabi.
FinancialsSep 09, 2026
Signet Jewelers to ‘Double Down’ on Blue Nile Amid Strong SalesThe jewelry retailer said it sees opportunity at higher price points, particularly in natural diamonds for bridal and fashion.
IndependentsSep 09, 2026
Sarah Leonard Fine Jewelers Closes After Nearly 80 YearsThe Los Angeles-based, family-owned jeweler was founded by Lenny and Sunny Friedman in 1946.
SourcingSep 09, 2026
Fura Gems Notes ‘Remarkable’ Interest in Larger Rubies at Latest SaleThe auction, held in Bangkok, was 96 percent sold by lot, with nearly 411,000 carats of Mozambiquan rubies sold.
