SSEF Warns Trade of Emerging Fraud Involving Re-Treated Emeralds

The Swiss Gemmological Institute (SSEF) has issued a warning to the gemstone trade regarding an increasing fraudulent practice in the emerald market, where gemstones are re-treated after laboratory testing and subsequently sold with reports that no longer accurately represent their condition.

According to SSEF, certain emeralds are stripped of clarity-enhancing substances such as oil, wax, or resin before being submitted for laboratory examination. This can lead to reports indicating “no” or “minor” clarity enhancement. Once certified, the stones are re-filled and marketed using the original report, potentially misleading buyers about their true quality and treatment status.

While clarity enhancement is a common and accepted practice for emeralds, international LMHC guidelines require full disclosure of both the presence and degree of treatment, as these factors have a significant impact on a gemstone’s value.

SSEF noted that the growing demand for untreated or minimally treated emeralds has contributed to the rise of this practice, with buyers often willing to pay substantial premiums for stones showing little or no clarity enhancement.

The institute emphasised that gemmological reports are valid only for the condition of a gemstone at the time it is examined. Any later alterations, including cleaning, refilling, or other treatments, may make the report outdated and potentially deceptive.

To safeguard buyers and traders, SSEF advises re-examining fissure-bearing emeralds before purchase, especially when reports are not recent. The institute also recommends exercising extra caution when a visually clean emerald is accompanied by a report stating no clarity enhancement.

SSEF further cautioned that similar concerns extend beyond emeralds to other fissure-bearing gemstones, including rubies, and called for heightened vigilance throughout the coloured gemstone industry.