Fraud Alert on Emeralds Treated After Testing
June 16, 26
(IDEX Online) - Emerald buyers are being warned about gems that have had their clarity enhanced AFTER they were laboratory tested.
Swiss Gemmological Institute (SSEF) warned yesterday (15 June) that it had seen a growing number of cases in which emeralds were submitted for certification, treated after certification, but then sold with the original lab report with disclosure of treatment.
Emeralds often have fissures filled with oil, wax, or artificial resin to improve their apparent clarity. The practice is legal but must be disclosed.
By treating gems after they have been tested, fraudulent actors are able to inflate their apparent value.
"The high-end market today favours stones that are only treated with minimal amounts of oil, or with no clarity modification," SSEF said in a trade alert.
"As a result, many emeralds that previously were treated with artificial resin are being chemically cleaned with strong solvents to remove the filler.
"Following the cleaning process, the emeralds that may now display prominent open fissures, are submitted to gem labs for testing."
Reports that are issued will likely state that no or only minor clarity modification was evident at the time of testing.
SSEF also warns of the same fraudulent practice among any other gem that has fissures.
Pics by SSEF show the same emerald after testing in 2024 and again in 2026, after it was cleaned and re-filled with artificial resin.