The lab said it has noticed emeralds it previously had tested resurfacing on the market with filler added post-testing, offered for sale with the original report that indicates little or no clarity modification.
Because most emeralds contain microscopic fractures known as fissures, the use of colorless fillers such as oil, wax, or artificial resin that reduce the visibility of the inclusions is a widely accepted practice in the trade.
However, treatment directly affects an emerald’s value, the lab stated, and disclosure of treatments, including the amount of filler used, is mandatory under the Laboratory Manual Harmonisation Committee guidelines.
Because the high-end market favors stones treated with minimal amounts of oil, or with no clarity modification, many emeralds previously treated with artificial resin are being chemically cleaned with strong solvents to remove the filler, SSEF explained.
After being cleaned, emeralds that display prominent open fissures are submitted to gem labs for testing. Reports are likely to state that no or only minor clarity modification was evident at the time of testing.
The fissures are then being refilled with either with oil or artificial resin after the lab report has been issued and then presented to third parties with a report that states “no or minor clarity modification,” a practice that constitutes fraud, SSEF said.
The report in these cases is misleading, because it no longer reflects the emerald’s current condition.
For this reason, SSEF said it emphasizes on its reports that the document describes the condition of the stone at the time of testing and makes no guarantee about the condition of the stone at any later date.
If fissure filler is detected, SSEF discloses its presence, the amount of filler used, and the identity of the filler substance, such as oil, artificial resin, or wax.
The lab made several recommendations to the trade for emerald buying, adding that any SSEF report can be verified for authenticity and validity on its website.
The lab encouraged buyers to check if a fissured emerald was retested by SSEF before buying it, especially in cases where the report is not recent or the stone appears “visually unusually clean.”
SSEF also warned buyers to be cautious of a clean-looking emerald accompanied by a “no clarity modification” report and encouraged them to have it re-tested.
Sellers should never circulate a report once a stone has been cleaned, refilled or otherwise altered; instead, they should submit the stone for a new report reflecting its current state before they sell it.
SSEF also noted that cleaned or heavily fissured emeralds are fragile and prone to chipping and must be handled with care.
The same treatments and risks apply to any gemstone that contains fissures, the lab added, with rubies being a notable example.
Contact SSEF for retests, to reissue reports, or for questions on emerald treatment and disclosure.
