Synthetic Diamond Screening Scales Up

While synthetic diamonds make up less than 1% of the market, unscrupulous dealers are already mixing in lab grown diamonds to melee parcels of natural diamonds.

Whichever side of the synthetics debate one might stand, all agree implementing the four D’s – Differentiation, Detection, Disclosure and Documentation – is vital to ensure consumer confidence in the natural product.

This need was put into sharp focus in 2012 when IGI International found some 600 undisclosed chemical vapor deposition (CVD) synthetic diamonds mixed in parcels of natural melee diamonds at its Antwerp lab.

Since then, the industry has worked to improve its screening of synthetics, with De Beers and the Gemological Institute of America (GIA) machines made available at bourses and for purchase.

Synthetic diamonds are a legitimate product category once there’s proper disclosure and they are marketed in a responsible way, Jean-Marc Lieberherr, CEO of the Diamond Producers Association (DPA), stressed in a recent panel discussion about synthetics.

We are more concerned about HPHT in the smaller sizes, as they are not easy to detect.

Sanjay Kothari of India’s Natural Diamond Monitoring Committee

Greater awareness

With more testing instruments available there have been fewer cases of undisclosed mixing in the past year, according to Vipul Sutariya, executive director for marketing at Dharmanandan Diamonds, a large supplier of melee.

Dharmanandan screens all the diamonds it sources with machines it operates in-house. It now sees this as an essential element in its production process as greater numbers of customers in the Far East and, increasingly, in the U.S. ask if their supply has been tested for synthetics.

With growing awareness of the issue a number of measures have been taken to guarantee the trade, and ultimately consumers, that the diamond they buy is in fact a natural diamond, explained Sanjay Kothari, spokesperson for India’s Natural Diamond Monitoring Committee.

Among those was a decision to ban synthetics from bourses, such as the Bharat Diamond Bourse and the Israel Diamond Exchange, and increasing the number of testing facilities. As more people are using the testing facilities, occurrence of undisclosed CVDs creeping into the market has diminished.

However, there has been an increase in undisclosed high pressure, high temperature (HPHT) treated smaller diamonds, according to Kothari. “We are more concerned about HPHT in the smaller sizes, as they are not easy to detect,” Kothari said. “Especially after these stones are set into jewelry.”

Building confidence

Manish Painter, general manager of Kiran Gems, a large-scale manufacturer of diamonds below 1 carat, noted that testing for synthetics in jewelry is more of a challenge. While a few testing machines have been launched this year, the technology is in early development and yet to gain the same acceptance as those checking loose stones.

While Kiran manufactures all of its supply rather than sourcing goods from the market, it still does random checks and gives a written assurance on every invoice that its diamonds are free of synthetics.

Providing such assurances is essential for the industry to protect itself against harmful elements and ensure its long-term sustainability, according to Kothari.

Image: IIDGR