A recent BuzzFeed News report features the story of Chrissy Clarius whose now-husband Jim purchased a certified 1-carat diamond solitaire engagement ring for her from Kay Jewelers in 2010; he reportedly paid nearly $4,300.
However, when she went to a local Kay store to have the ring repaired in February, employees could not find the certification number inscribed on the diamond.
Suspecting something was wrong, Clarius had the stone assessed by two other jewelers who independently agreed that it was made of a look-alike material called moissanite.
She ultimately returned to the Kay store and confronted the manager who, according to her, implied that a swap may have happened during repairs made elsewhere.
Clarius has since filed a police report and a consumer complaint, but her experience does not seem to be an isolated incident.
In fact, BuzzFeed News posted a story last month about a woman whose custom-designed engagement ring simply disappeared during a repair and another who had a diamond fall out of a replacement ring.
The company's Facebook page also contains numerous complaints about customers receiving lower-quality stones, stores trying to cover up lost rings, and poor workmanship in general.
A company representative issued a statement to Refinery29 saying that it is "actively reviewing this issue."
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The Cartier tiara, worn on her wedding day to Prince William, and the matching earrings given to her by her parents.
Photo: UK Press via Getty Images
Her diamond and sapphire engagement ring.
Photo: Chris Jackson/Getty Images
The Lotus Flower tiara, worn in 2013 to a Diplomatic Reception with Prince William.
Photo: Splash News
The ruby and diamond necklace and bracelet, which the Duchess wore to the Sun Military Awards in December 2011.
Photo: ARTHUR EDWARDS/AFP/Getty Images
A closer look at the necklace worn to the Sun Military Awards.
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The Nizam of Hyderabad necklace, on loan from Queen Elizabeth II, worn while attending an event at the National Portrait Gallery.
Photo: AP Photo/Alastair Grant
The glittering diamond and emerald earrings with matching bracelet worn during the St. Andrews reception at the Metropolitan Museum of Art in New York.
Photo: AP Photo/Jason DeCrow, Pool
The sparkling diamond fern brooch worn during the royal tour of Australia and New Zealand, when the royal family touched down in New Zealand.
Photo: Samir Hussein/WireImage
These vibrant blue sparklers, borrowed from her mom, Carole Middleton, and worth nearly $20,000.
Photo: Samir Hussein/WireImage
The Lotus Flower Tiara, again for a state reception with the President of China, paired with two diamond bracelets -- one called The Wedding Gift, with geometric elements, and the second, which has also been worn as a necklace. All of Kate's jewels were borrowed from the royal vault.
Photo: Dominic Lipinski/PA Archive
The Cambridge Lover's Knot Tiara, worn during a diplomatic reception at Buckingham Palace, one of the late Princess of Wales's favorite tiaras.