The Gemological Institute of America (GIA) has asked customers to return a number of colored diamonds for reassessment, suspecting that a treatment might have gone under the radar.
The organization will reevaluate certain diamonds with “green or greenish” in the color grade, a spokesperson told Rapaport News last week. The recall applies to reports it issued between January and June 2020. The GIA declined to reveal how many stones were affected or to provide their report numbers.
“Recent research and investigation into potential treatment methods caused us to request the return of the subject diamonds for further analysis,” the spokesperson said.
The institute informed customers about the issue around six weeks ago, and is in the process of collecting and reassessing the diamonds. Some stones could get an “undetermined” ruling, while others may require further testing, the spokesperson explained. Many diamonds had already come back with their natural-color statuses confirmed, market sources said. The GIA bases its conclusions on the “state of knowledge and criteria in place at the date of examination,” it added.
Sources estimated that the number of reports under review was close to 100 and could be much higher. The GIA did not specify the nature of the possible treatment. The case is unrelated to the recent discovery of a treated fancy-color diamond on which the institute reported in the latest edition of its academic journal, Gems & Gemology.
“GIA has been investigating the cause of color in diamonds and other gem materials for nearly 70 years,” the spokesperson continued. “Among GIA’s earliest area of research was determining origin of color of green diamonds, which remains even today one of the most difficult areas of gemology. The research process is dynamic, and we recently discovered new information that may provide new insights about the origin of color of the group of diamonds that we have requested to be returned for review.”
The GIA is already dealing with a wider grading backlog following a rebound in market activity in recent months. The organization is operating with as much capacity as local Covid-19 rules allow, using weekends, second shifts and overtime, the spokesperson said.