Source: trade alert issued by the Swiss Gemmological Institute (SSEF), reported by Rapaport and DiamondWorld, 2026.
SSEF, one of the world’s most respected gemstone testing laboratories, has issued a trade alert warning the colored gemstone industry of a troubling practice: emeralds that have had fillers such as oil, wax, or resin removed before lab testing — earning a report of “no” or “minor” clarity enhancement — are later re-filled after certification and sold using that original, now-inaccurate report.
The institute is urging buyers to verify the legitimacy of any certificate, have stones rechecked at the point of sale rather than relying on paperwork alone, and handle cleaned or heavily fissured emeralds with extra care, since they are more fragile once treatments are removed.
Murat Koç’s Take
“This is exactly why a certificate should be treated as a starting point, not the final word — especially with emerald, which is one of the more heavily treated gemstones in the trade by nature of its inclusions. Emerald is a beautiful, deeply traditional stone for both fine and high jewelry, and the vast majority of the trade handles it honestly. But a report issued even a year ago doesn’t guarantee the condition of the stone in front of you today.”
“For any centerpiece colored stone — emerald most of all — I recheck condition before it goes into a setting, regardless of what paperwork accompanies it. It takes a little longer, but it’s the only way to be honest with a client about exactly what they’re buying.”