HPHT Under the Gavel

On Tuesday, representatives from the major gemological labs and industry organizations gathered together at the New York Diamond Dealers Club to debate the thorny issue of High-Pressure High-Temperature (HPHT) treated diamonds.

Since the process first came to the forefront of the industry in the late nineties, the matter of disclosure of HPHT treated diamonds has given cause of concern to many throughout the industry. While at present Lazare Kaplan's/GE Bellataire line is the only official line of HPHT diamonds on the market, there has been an increase, especially over the past six months, of a greater number of treated diamonds on the market.

Officially all HPHT diamonds when sold by dealers must be disclosed as having undergone treatment, but increasingly there are cases of HPHT diamonds submitted for grading without prior disclosure. It was the issue of how the gemological labs certify these, as well as prior disclosed HPHT diamonds, that would prove to be the overwhelming point of debate throughout the day's talks.

Representatives of the labs present at the meeting (GIA, IGI, EGL, HRD and AGS) all agreed that well over 90 percent of all HPHT diamonds are detectable at best, or are flagged as undetermined. ‘Undetermined’ is the euphemism used for stones that according to the lab's examination may or may not have been HPHT treated.

At present, all the labs, bar the AGS, will only certify a HPHT stone (disclosed as such on their grading certificate) if the stone is laser-inscribed on the girdle as HPHT. If, they say, the client refuses the lab permission to laser-inscribe the stone, then they return the diamond without certification. However, for many present at the meeting this is not guarantee enough.

One issue that proved to be a sticking point during most of the day was the exact wording on a lab's report over what precisely is HPHT. Some referred to HPHT on their certificates as a stone that has undergone HPHT treatment to 'improve' its color. Others describe the process as 'altering' the color of a stone.

By the end of the meeting, a recommendation was made to implement a standardized wording throughout all laboratories describing on their certificates the effect of HPHT on a stone. 'Improved' or 'enhanced' were considered to be too ambiguous, with terminology such as 'modified' 'altered' or 'changed' preferred as describing the effect the process has on the color (and in some cases clarity) of the diamond.

Another recommendation called for a mandatory laser inscription of all certified HPHT stones.

“We need detection, disclosure and co-operation,” stated the host of the meeting, DDC President Jacob Banda. “It's all about ensuring consumer confidence,“ he urged. The outcome of this meeting proved that while there may be disagreements over the minutiae of HPHT, all were unanimous that full disclosure of HPHT is paramount and steps must be taken to ensure that no HPHT treated stones reach the consumer without such disclosure on the certificates and the diamond itself.