Fake Diamond Listings? UK Jewellers Warn Against Moissanite Mislabeling in Online Marketplaces
UK jewellers are warning consumers about a growing number of online listings that misrepresent moissanite as lab-grown diamonds. The alerts come amid rising reports of buyers receiving moissanite stones that were marketed as diamonds on platforms such as eBay, AliExpress, and unregulated online boutiques.
Moissanite, a lab-created gemstone renowned for its exceptional brilliance and affordability, is gaining popularity in the UK. However, industry experts say the visual similarity between moissanite and diamond is being exploited by some sellers who intentionally mislabel products to command higher prices.
The issue has gained traction as consumer confusion becomes more visible. Google Trends data shows a significant increase in UK-based search queries such as “moissanite vs diamond,” “Is moissanite fake,” and “moissanite engagement ring UK” over the first half of 2025.
Concerns are echoed across online forums. On Reddit’s r/EngagementRingsUK, users have questioned the legitimacy of stones they believed to be diamonds but later suspected to be moissanite. “I was told this was a lab diamond, but now I’m not sure—how can I check if it’s moissanite?” one user posted.
Similar discussions are occurring on r/Moissanite, where users report stones failing thermal diamond testers—an issue consistent with moissanite’s different physical properties.
On Quora, UK users have raised questions about moissanite being marketed as lab-grown diamonds, with some reporting deceptive listings on sites that do not offer gemological certification.
Industry professionals are now calling for regulatory intervention. Many are advocating for stricter guidelines requiring clear gemstone disclosure and mandatory third-party certification, such as from the Gemological Institute of America (GIA) or the International Gemological Institute (IGI), for all diamond and diamond-alternative sales.
“There is currently no obligation for sellers to disclose the difference between moissanite and lab-grown diamonds, especially on global marketplaces,” said a spokesperson for a London-based jewellery retailer. “This lack of regulation creates a risk of consumer fraud.”
Retailers have also urged online platforms to verify gem listings before publishing and to penalize vendors that repeatedly mislabel their products. While moissanite is a legitimate gemstone in its own right, its use as a stand-in for diamonds—without full disclosure—is seen as a growing threat to consumer trust in the jewellery market.
The issue is further complicated by trends on social media platforms such as TikTok and Pinterest, where moissanite jewellery has been promoted widely for its affordability and sparkle. These posts often fail to clarify that moissanite is not a diamond, contributing to public misunderstanding.
In response to the confusion, UK jewellers have begun launching consumer awareness campaigns focused on how to verify gemstones, read certificates, and use both thermal and electrical testers—since moissanite can mimic diamonds in some basic heat tests but not in electrical conductivity.
Until comprehensive regulations are introduced, experts advise consumers to shop only with verified sellers, request lab reports for any stone advertised as a diamond, and treat any product listed without certification as potentially misrepresented.
The Advertising Standards Authority (ASA) and Trading Standards have not yet issued formal guidance specific to moissanite labelling, but industry groups are expected to petition for legislative updates later this year.
