Lead Glass-Filled Lab-Grown Ruby Submitted to GIA
Though it’s unclear why someone would treat the material in that way, it’s important gemologists know it exists, the lab said.
According to a lab note from Forozan Zandi in the spring 2021 issue of “Gems & Gemology,” the stone was submitted to the GIA Carlsbad lab for identification.
Zandi said that while it’s common for the lab to receive lead glass-filled natural rubies, to their knowledge only one other lab-grown example has ever been submitted.
The recently submitted ruby was transparent to semi-transparent, oval mixed-cut, and weighed 3.53 carats.
GIA performed the standard gemological tests on the stone, finding that it showed the properties of a ruby, including a refractive index of 1.761–1.769, a birefringence of 0.008, a specific gravity of 4.01, a uniaxial optic figure, and a characteristic ruby spectrum via a spectroscope.
It also put the stone under magnification, which helped the lab confirm it was filled, according to the note.
With lead glass-filled corundum, the filling material has a refractive index very close to that of the host material to reduce the appearance of fractures. GIA said it’s effective and helps improve clarity of even very low-quality material to help make it marketable.
Fortunately, it’s also easily detected under magnification, the lab added.
The lab-grown ruby in question showed a couple of conclusive identifying characteristics for the treatment when put under the microscope: orange and blue flash effects and gas bubbles trapped in the fractures.
Magnification, however, didn’t reveal any inclusions that would indicate a natural or lab-grown origin.
But when it viewed curved growth lines in the DiamondView, which looks at surface fluorescence by illuminating with shortwave ultraviolet light, the lab saw the striae as chalky luminescent bands, confirming the stone was lab grown.
Ultimately, the lab note concluded: “While it is unclear why anyone would go to the trouble to treat a synthetic ruby with lead-glass filling, gemologists should be aware that such material does exist in the trade.”
The Latest
For her annual Halloween story, Associate Editor Lenore Fedow pairs fine jewelry with classic and contemporary Halloween costumes.
Sales fell 15 percent for the luxury conglomerate in the third quarter, led by a 26 percent drop in sales for flagship brand Gucci.
The education offerings include a diamond cutting demonstration, a session with JVC President Sara Yood, and a seminar on AI.
From protecting customer data to safeguarding inventory records, it's crucial to learn how to tackle cybersecurity challenges.
The book features new styles and revived favorites.
Aimed at a generation that emphasizes self-care and mental health, “Worth the Wait” breaks new ground in the world of diamond advertising.
Editor Lauren McLemore immersed herself in New York Bridal Fashion Week to better understand the role fine jewelry plays on the big day.
This fall, sharpen your skills in jewelry grading, quality control and diamond assessment.
The jeweler shared her change of heart on lab-grown diamonds and why she keeps them separate from natural diamonds in her business ventures.
The New York-based brand is expanding outside of the U.S., with a pop-up shop in London and plans to distribute internationally.
They’re available through a retailer that sells luxury products inspired by the lifestyle of Batman’s billionaire civilian persona.
The watchmaker is selling 1,000 “Waterbury” watches for $1 each in celebration of its 170th anniversary.
Launched by De Beers in 2018, the program aims to develop a responsible sourcing model for the artisanal/small-scale diamond mining sector.
The new “Ouche” collection brings sculptural designs to the brand, while the expanded “Daystar” collection brings a rainbow of colors.
The auction house said the gemstone could fetch up to $5.5 million at next month’s sale.
From prioritizing the customer experience to optimizing inventory, columnist Emmanuel Raheb shares the keys to a successful holiday season.
Journalist Priya Raj plans to use the scholarship funds to further her media qualifications and amplify marginalized communities.
It marks the first championship win in the team’s 28-year history.
The Arkansas-based jeweler’s first store in the state’s northwest region is set to open next year.
It will start with rough diamonds that are larger than 1.25 carats and later expand to rough diamonds that are above 1 carat.
The capsule collection is inspired by friendship and connection, with a nod to ‘80s fashion.
The New York socialite’s elegant, transformable piece from the 1960s is headed to auction later this month.
Texas jeweler Susan Eisen and NAJA’s Gail Brett Levine discuss how lab-grown diamonds have altered the landscape for jewelry appraisers.
On the verge of retirement, Kennedy recounts the most stressful stretch of his time at JSA and reveals what he’ll miss about the industry.
Signet Jewelers CEO Gina Drosos’ secrets to success are listening to her team and leaning on data to make decisions.
Part of the Welsh singer’s extensive jewelry collection, the bathtub-shaped Cartier watch went for nearly $72,000 at Sotheby’s Paris.
The event is slated for Oct. 17-19.