Two “altered” Gemological Institute of America lab reports were recently spotted on the market, GIA acknowledged recently.

The Institute made the statement after Gübelin Gem Lab issued an alert warning that it had seen a 2.00 ct. HPHT-treated diamond “that was accompanied by a report from the GIA Laboratory, and did not mention any treatment. The report is a suspected forgery. … The Gübelin Lab has seen a similar, probably forged, report for a top-quality diamond exceeding 4.00 carats.”

The GIA statement said, “GIA reports include a number of important security features and safeguards, some apparent and others more subtle.”

It noted that careful scrutiny can sometimes guard against such fakes. In this case, the reports contained a misspelling of the word fluorescence.

It also said its Web site had a Report Check feature to double-check a report’s accuracy. It can be found at www.gia.edu/reportcheck.

This is not the first incident of this type. In 2004, GIA warned that two forged reports had been spotted in Antwerp, Belgium.