GIA Edging Toward Solving Mystery Color Treatment Case

02/06/2015 07:40

The GIA is close to working out what the mystery treatment was aimed at temporarily improved the color of some 500 diamonds submitted for the most part to its Israel lab, GIA President and CEO Susan Jacques said at the annual Rapaport conference on grading standards on May 31. Phil Yantzer, vice president of GIA’s Carlsbad lab services, said: “We know what is being done, but we don’t know how it is being done." Most of the stones were “off-color,” however since such diamonds are common, that didn’t raise an alarm. He declined comment on whether it was a coating, saying that GIA graders regularly check for coatings.