MajorsJul 18, 2025
Lewis Heyman on Sourcing Gemstones, Post-Retirement PlansHe retired last month after 28 years traveling the world to source the very best gemstones for his family’s jewelry business, Oscar Heyman.
GradingMay 22, 2019
GIA Spots Second Natural Diamond with Lab-Grown Layer
The stone is 0.64 carats and graded as a fancy grayish-greenish blue.
Gemological Institute of America researchers said the gray and blue components from the lab-grown layer of this diamond combined with the yellow from the natural substrate to create the color, fancy grayish-greenish blue. (Photo credit: Robison McMurtry)
Carlsbad, Calif.—GIA researchers recently spotted a second natural diamond with a lab-grown layer that added weight and improved the color, and warned that it could mean the trade will see more of these kind of composites.
According to an article by Troy Ardon and Garrett McElhenny in the spring 2019 edition of “Gems & Gemology,” the presence of both boron- and nitrogen-related defects—which are rarely seen together in natural diamonds—tipped them off there was something unusual about the stone.
The DiamondView fluorescence image of the diamond—a 0.64-carat fancy grayish-greenish blue cushion modified brilliant—showed a blue hue caused by the “cape” peak (nitrogen defect) and natural growth features.
The crown image, however, revealed a greenish-blue color common to boron-bearing diamonds and the dislocation patterns typically seen in diamonds grown using the chemical-vapor deposition (CVD) process.
In addition, a side view shows a distinct layer between the natural substrate and the CVD-grown portion of the stone. 
“These two distinct fluorescence patterns—the greenish-blue from the CVD layer and the darker blue from the naturally grown layer—prove that a layer of CVD synthetic diamond was grown on a natural substrate,” the article states.
A similar diamond, a 0.33-carat fancy blue that was also Type IIb with a CVD layer, was submitted to GIA in May 2017.
The CVD layer on this latest diamond is substantially thicker, 200 microns (approximately the thickness of two strands of human hairs) vs. 80 microns on the 0.33-carat diamond evaluated two years ago, and GIA noted that seeing a second example of this same type of composite could signal a new type of product entering the market.
The lab would not say if both diamonds came from the same client.
GIA also declined to comment on how the stones were submitted—as natural diamonds, or as natural/lab-grown composites—but did note that clients submitting goods are required to disclose all known treatments as well as whether a stone is natural or man-made.
To see more from the spring 2019 edition of “Gems & Gemology,” the Gemological Institute of America’s quarterly research journal, visit GIA.edu.
More on Grading
The Latest
TrendsJul 18, 2025
Piece of the Week: CCWW Designs’ Shell Charm NecklaceThe charm necklace features six nautical charms of shells and coral that founder Christina Puchi collected on Florida’s beaches.
MajorsJul 18, 2025
Plumb Club Elects New Board MembersThe organization elected its youngest vice president as it looks to draw in fresh talent.
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.
TechnologyJul 18, 2025
Brad Campbell, John Liebler Join Clientbook’s Executive Team Campbell joins the company as vice president of business development while Liebler is the new vice president of operations.
Weekly QuizJul 17, 2025
This Week’s QuizTest your jewelry news knowledge by answering these questions.
CollectionsJul 17, 2025
2026 Winter Olympic Medal Design Symbolizes UnityThe medals feature a split-texture design highlighting the Games’ first time being hosted by two cities and the athletes’ journeys.
Supplier BulletinJul 17, 2025
The INSTORE Jewelry Show 2025: Your Holiday Preparations, All Wrapped Up! Sponsored by The INSTORE Jewelry Show 2025
Brought to you by
Jewelers of America is Headed to Las Vegas for JCK 2025The countdown is on for the JCK Las Vegas Show and JA is pulling out all the stops.
SurveysJul 17, 2025
The Most Recommended Brands in the World, According to YouGovGlobally, travel and transportation brands reigned, while in the U.S., alcoholic beverage companies and a lingerie brand took the top spots.
IndependentsJul 17, 2025
Gina Ferranti of GiGi Ferranti Jewelry Dies at 59The Brooklyn-based jewelry designer is remembered as a true artist and a rare talent.
SourcingJul 17, 2025
Rio Tinto Names New CEO, Production Rises at DiavikProduction at the mine in Canada’s Northwest Territories topped 1 million carats in Q2, the third consecutive quarter of growth.
Events & AwardsJul 17, 2025
JA to Hold Learning Workshops This FallA new slate of Learning Workshops will take place in Oklahoma, Mississippi, and Georgia.
SurveysJul 16, 2025
Signet Jewelers Falls Lower on NRF’s ‘Top 100’ Retailers ListThe middle class is changing its approach to buying jewelry and affordable luxury goods, the NRF said.
FinancialsJul 16, 2025
Richemont’s Jewelry Sales Up 7% in Q1It marks the third consecutive quarter of growth for Cartier, Van Cleef & Arpels, Buccellati, and Vhernier.
WatchesJul 16, 2025
The Top-Selling Rolex Models of the Last 15 Years, According to Bob’s Watches The reseller’s market trends report, based on its sales data, also shows exactly how much Rolex prices have jumped since 2010.
AuctionsJul 16, 2025
Christie’s To Honor Dinh Van With ExhibitionThe auction house will be hosting a retrospective paying tribute to jeweler Jean Dinh Van and his company’s 60th anniversary.
IndependentsJul 16, 2025
Clyde Duneier Ushers In Fourth GenerationJake Duneier and Danielle Duneier-Goldberg have stepped into the roles of CEO and president, respectively.
CollectionsJul 15, 2025
Boucheron’s New High Jewelry Calls Attention to Nature’s ImpermanenceThe “Impermanence” collection contemplates nature through the Japanese art of Ikebana (flower arranging) and philosophy of wabi-sabi.
MajorsJul 15, 2025
James Avery Expands to 2 More StatesThe Texas-based jewelry retailer has set up shop in Tennessee and Arizona.
Events & AwardsJul 15, 2025
Neiman Marcus Vet Joins Couture as Brand Director Eric Ford will step into the role, bringing with him decades of experience.
MajorsJul 15, 2025
Ben Bridge Jeweler Acquires Olympic ManufacturingIn addition to improved capabilities, the acquisition will allow the jeweler to offer support to other independent jewelers.
CollectionsJul 15, 2025
Guzema Debuts First Colored Gemstone JewelryThe “Celestial Blue” capsule collection campaign features Olympian Kateryna Sadurska.
MajorsJul 14, 2025
Nanis Opens First StoreThe seasonal store, located in Mykonos, Greece, offers exclusive events, personal styling, and curated experiences.
IndependentsJul 14, 2025
It’s the Summer of Love at Long’s JewelersThe New England jeweler is hosting a bridal event for the month of August.
SourcingJul 14, 2025
Ethical Gem Fair Heads to SeattleThe trade-only event will host its debut fair in the Emerald City later this month.
Events & AwardsJul 11, 2025
The Edge’s Annual Conference Returns in SeptemberIts sessions will focus on inventory strategies, staff performance, retention and acquisition, emerging market trends, and more.
CollectionsJul 11, 2025
Piece of the Week: Miseno’s ‘Arco’ EarringsFor its 10th anniversary, Miseno designed the “Arco” earrings based on the Arco Felice, an arch conceptualized in A.D. 95 in Miseno, Italy.
