WatchesApr 10, 2026
These Watches Have Increased in Value the Most Since 2018, Says Chrono24The top-performing watch models may be surprising, with Rolex and several popular pandemic-era picks notably absent from the top 20.
GradingAug 15, 2018
Glued-Together Diamond Turns Up at GIA
The stone had been broken in half and put back together with an “unknown adhesive,” and couldn’t be graded by the Carlsbad lab.
A face-up photo of the glued-together diamond recently spotted by graders in the GIA lab in Carlsbad (Photo by Robison McMurtry/GIA)
Carlsbad, Calif.—The Gemological Institute of America said its Carlsbad lab recently received a diamond that had broken in half and been repaired with an adhesive of some sort.
In the summer 2018 issue of Gems & Gemology, GIA research associate Troy Ardon wrote a lab note about a 1.38-carat marquise-cut diamond submitted to the laboratory for colored diamond grading services.
Graders initially noted large fractures and a large cavity on the table. After careful examination under a microscope, they discovered that the stone had been broken in half and then repaired with an “unknown adhesive,” a method the lab noted was unusual.
The GIA said there were a number of factors that hinted to it being broken and put back together imperfectly, the first being a large fracture from crown to pavilion showing a “sizeable gap” throughout the diamond.
The fracture indicated it was a repair, rather than two separate diamonds glued together to make a larger stone, because it had an irregular surface, according to Gems & Gemology.
From a certain angle, graders could also see large air bubbles trapped in the fracture.
Additionally, the facets that the fracture transected showed “slight to moderate” misalignment, which the GIA confirmed can’t happen during the polishing process.
The GIA said polish lines on the pavilion facets contained a pattern that would’ve lined up if it wasn’t for the fracture that separated them, demonstrating that the breakage occurred after the diamond had been at least somewhat polished. Beyond that, it’s not possible to tell when the damage happened, the lab said.
While the application of glue to diamonds to form a diamond-diamond doublet has been done before, the GIA noted that it has never seen a broken diamond repaired with adhesive in this manner.
The lab was not able to grade the diamond because the 4Cs don’t apply to “composites” like this. For example, the carat weight would actually represent the sum of the two diamond weights plus that of the adhesive.
Editors' Picks
Sponsored by
More on Grading
The Latest
CollectionsApr 10, 2026
Ophelia Eve’s Toggle Pendant Holds Your SecretsThe “Scroll” toggle pendant, our Piece of the Week, opens to reveal a hidden message, mantra, or love letter written on washi paper.
ColumnistsApr 09, 2026
Jewelry Demand Isn’t Stronger, Prices Are Just Higher Jewelers who misinterpret the state of the jewelry market risk employing the wrong retail strategy, cautions columnist Sherry Smith.
Brought to you by
Protect Your Customers and Your BusinessYou deserve to know what you are selling–to protect your customers as well as your business and your reputation.
MajorsApr 09, 2026
Tiffany & Co. Promotes Nathalie Verdeille to SVP, Chief Artistic OfficerIn her newly expanded role, she will continue to oversee the jewelry category, as well as watches, home, and accessories.
Weekly QuizApr 09, 2026
This Week’s QuizTest your jewelry news knowledge by answering these questions.
WatchesApr 09, 2026
Jacob & Co. Rolls Out Its Sequel to ‘The Godfather’ Musical Watch“The Godfather II” watch plays two melodies from the mob film’s score, “The Godfather’s Waltz” and “The Godfather Love Theme.”
Events & AwardsApr 09, 2026
JCK Announces Jesse Itzler as 2026 Keynote SpeakerOrganizers have also introduced the new JCK Talks Signature Series, as well as an offering of watch-focused workshops and lectures.
Brought to you by
Is This You? Every Jeweler Has This Problem; We Have the Solution.Every jeweler faces the same challenge: helping customers protect what they love. Here’s the solution designed for today’s jewelry business.
SourcingApr 09, 2026
AGA To Honor ‘Quiet Leadership’ With New AwardThe Alan Hodgkinson Medal recognizes gemologists who are consistently generous with their time and expertise.
WatchesApr 09, 2026
Oris Names New CEO, CFOThe Swiss watchmaker is changing up its executive leadership team as part of a restructuring.
CollectionsApr 08, 2026
Hearts On Fire Celebrates 30 Years By Asking a QuestionThe “What’s Your Signature?” campaign invites women to think about how they see themselves.
SourcingApr 08, 2026
Sale of 42-Carat Blue Diamond Gives Petra a Boost in Q3The big diamond’s sale added to the company’s revenue though the market remains “challenging” overall, particularly for smaller goods.
Events & AwardsApr 08, 2026
AGS Confluence Returns with AI, Sustainability SessionsRob Bates of The Jewelry Wire will also moderate a panel on the state of the jewelry industry during the virtual event.
Events & AwardsApr 08, 2026
TJS to Honor 2 Longtime Former Stuller EmployeesThe Jewelry Symposium will honor two industry veterans with lifetime achievement awards at its upcoming May event.
TrendsApr 08, 2026
Amanda’s Style File: April’s Brilliant Birthstone With their durability, brilliance, and beauty, diamonds are the perfect stone for everyday birthstone jewelry.
MajorsApr 07, 2026
QVC Group’s Latest Filing Calls Its Future Into QuestionThe retailer failed to file its annual report on time and said it may issue a going concern warning.
ColumnistsApr 07, 2026
Peter Smith: A Tip to the Post Office on Workplace CultureSmith recounts a recent trip to the post office that included an uncomfortable, embarrassing, and public exchange between two employees.
CollectionsApr 07, 2026
Nerd Out Over Gemology Geek’s First Jewelry CollectionFounder Erica Silverglide has designed 35 colorful pieces set with fluorescing gemstones for the brand's first finished jewelry offering.
CollectionsApr 07, 2026
Ukrainian Jewelers Highlighted In New Book“Ukrainian Jewelry | Contemporary Jewelry and Art Jewelry from Ukraine” features 33 contemporary Ukrainian designers and studios.
CollectionsApr 06, 2026
Fope’s New Jewelry Debuts Are Golden“The Golden Now” campaign celebrates the here and now with the brand’s signature styles and a selection of its new pieces.
MajorsApr 06, 2026
Kecia Caffie, Corinne Bentzen No Longer With Signet JewelersSignet confirmed that Caffie, president of Zales and Banter, and Bentzen, who headed Blue Nile, have left the company.
CollectionsApr 06, 2026
Historian Tanzy Ward Pens Book on Black Victorians’ JewelryThe antique jewelry dealer talks about the importance of including Black Americans in jewelry history and preserving their stories.
SourcingApr 06, 2026
Gemfields Reports $51M Loss in 2025Both its mines faced challenges last year, from operational issues to disruptions in the market.
CollectionsApr 03, 2026
Taylor Swift’s ‘Elizabeth Taylor’ Video Puts Jewelry Front and CenterIconic pieces, like the Mike Todd Diamond Tiara, appear in the superstar’s new music video for her song inspired by the actress.
MajorsApr 03, 2026
Saks Global Says It Will Emerge From Bankruptcy This SummerThe luxury retailer, which went Chapter 11 in January, announced Thursday that it has secured $500 million in exit financing.
Events & AwardsApr 03, 2026
JCK Luxury, NouvelleBox Partner on New Designer BallroomThe NouvelleBox ballroom will feature independent jewelry designers, including Lene Vibe, Wyld Box Jewelry, and Kiaia Limited.
CollectionsApr 03, 2026
Buddha Mama Brings Its ‘Moon’ Locket To DallasThe one-of-a-kind locket, our Piece of the Week, opens to reveal three hidden images to keep close to your heart.
