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Vallabhbhai Shamjibhai Patel tells about the ongoing construction of the Surat Diamond Bourse

The under-construction Surat Diamond Bourse (SDB) is India's second diamond trading hub based at Surat, Gujarat, spread across 35.54 acres with more than 4,000 offices for national & international traders. On the onset, the project which...

18 june 2018

The strategy of regulating the Russian jewellery industry

At the General Meeting of the Russian Jewellers Guild Association held in April, two principally important documents were adopted: The Strategy of Regulating the Jewellery Industry of Russia and The Charter of a Good Faith Taxpayer. Besides, the issues...

13 june 2018

Our first priority is to better understand artisanal and small-scale mining - Elodie Daguzan

The Diamond Development Initiative (DDI), the organization dealing with the traditional diamond mining, recently announced the appointment of Élodie Daguzan as its first Goodwill Ambassador. Ms. Daguzan, who currently works as head of communication...

04 june 2018

Zimnisky on De Beers’ Lightbox: It’s a strategic, bold move that will benefit the entire natural diamond industry

De Beers shocked all and sundry end of May when it announced the launch of a new company called Lightbox Jewelry, which will market a new brand of laboratory-grown diamond jewellery in September. This effectively meant that the group had departed from...

01 june 2018

Tracking the provenance and lifecycle of a product is a natural and necessary evolution in our industry

A senior executive with a demonstrated history of working globally at management and board levels, Marcus ter Haar has been the Managing Director at Okavango Diamond Company (ODC), Botswana for about 10 months now, prior to which he held the...

28 may 2018

Chinese lab spots stone with CVD coating

11 december 2017
A Chinese gemological laboratory has identified a well-concealed synthetic-diamond coating that bolstered the size of a small natural stone.While the lower part of the stone was a colorless, natural diamond, the upper section, including the crown and the top of the pavilion, contained a layer of diamond created using chemical vapor deposition (CVD).
CVD coatings have been present in the industry for many years, but according to the Beijing-based National Gemstone Testing Center (NGTC), which detected the stone said in a statement: “CVD overgrowth, which significantly influences the weight and size of the diamond, is still rarely reported up to now,” and therefore a major concern for the trade.
NGTC also stated that the coating over the brilliant-cut, 0.11-carat, near-colorless diamond was hard to detect, with no features betraying its existence visible using a microscope. The layer was thicker, perhaps indicating an improvement in growth technique there were no blemishes on the stone resembling needle marks.
NGTC gemologists were able to identify the overgrowth with spectroscopic analysis, as well as images were taken using DiamondView technology. However, the lab did not mention how much weight the coating added to the diamond.

Aruna Gaitonde, Editor-in-Chief of the Asian Bureau, Rough & Polished

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