SSEF warns of emeralds refilled after testing, urges disclosure checks

A clean-looking emerald can turn deceptive fast: fissures can be cleaned and refilled with artificial resin or oil in a matter of minutes after laboratory testing, then resold with an older report showing little or no clarity modification. The Swiss Gemmological Institute SSEF issued its trade alert on June 15, 2026, after recent cases.

The reports describe only the condition of a stone at the time it was tested, not its condition later. In those cases, emeralds were tested, received reports indicating little or no clarity modification, then were cleaned and refilled before being offered again. Dr. M. S. Krzemnicki and the Basel-based lab urged the trade to verify report authenticity and validity before any transaction, especially when a stone looks cleaner than its visible fissures suggest.

Fissures are common in emeralds, and filling them with colorless substances such as oil, wax, natural resin or artificial resin has long been accepted trade practice. Disclosure is mandatory under CIBJO and the Laboratory Manual Harmonization Committee guidance, because treatment directly affects value. The high-end market now favors emeralds with minimal oil treatment or none at all, which creates an incentive for some owners or dealers to remove earlier resin fills chemically and refill the stones after laboratory testing.

Many emeralds are resubmitted more than once because fissures are cleaned and filled repeatedly, and a stone resubmitted for a recheck or report update receives a new report number. Since March 2016, SSEF has used more descriptive wording in emerald clarity-modification reports to distinguish stones with no fissures from those with fissures but no filler detected at the time of testing.

Ask for current disclosure, verify the report number, and retest fissured emeralds immediately before purchase if the report is not recent. Report photos represent the stone as submitted, not its later state.