Majority of Diamonds in GIA Hacking Case Still Not Returned

RAPAPORT... Only 175 of the 1,042 diamonds whose Gemological Institute of America (GIA) reports were invalidated last month following a hacking incident have been returned for examination, the organization said.

“It is imperative that all of the diamonds and their reports be returned to GIA for examination to remove the fraudulently altered reports from the market,” the GIA said in a statement November 25.

The diamonds’ color and clarity reports were changed by hackers. The GIA nullified the certificates and requested on October 23 that anyone in possession of any of the stones or reports return them immediately for a free examination. The group is offering a no-cost confirmation service through the end of January for any diamond grading report originally issued between November 2014 and October 2015.

The GIA continues to work closely with its database support contractor Tata Consultancy Services (TCS) and the Indian police to continuing investigating the case, it said. Two former TCS employees have been arrested and the client accounts through which the diamonds were submitted have been suspended.

Separately, 10 companies remain suspended by RapNet, the Rapaport Diamond Trading Network, pending further investigation. The members were also suspended by GIA for allegedly participating in the hacking scheme.

Lucara diamond miner recovered a 1,111 carat rough diamond

Lucara Diamond Corp has recovered a 1.111 ct diamond at the Karowe mine in Botswana.

The second largest gem quality stone ever mined is the most important discovery is recent history.

The diamond second only to the legendary Cullinan diamond, which was recovered in South Africa in 1905 and weighed 3,106.75 carats.

The 1.111ct rough diamond is a white Type IIa diamond considered the purest form of diamond.

Source: DCLA 

‘Harsh’ prison sentences given in bribery case

November 17, 2015

Antwerp--The Correctional Court in Antwerp handed down “extremely harsh” sentences and levied “substantial fines” against four diamond traders accused of bribing a grader at HRD Antwerp to give their diamonds higher color grades than they deserved.

The Antwerp World Diamond Centre (AWDC) announced the sentences via a press release circulated Monday titled “No mercy for those involved in certification fraud.”

On Tuesday, an AWDC spokesman said that the traders received up to 30 months in jail, 15 of which is effective immediately.

Although the AWDC is not releasing their names, the spokesman did reveal that three of the traders are from India--from Surat, Bhiwandi and Mumbai--and were managers of Belgian diamond companies. The fourth is from Sierra Leone.

The grader, whose name also is being withheld, received a “heavy” sentence as well, 18 months in jail, 9 of which is effective immediately, and a substantial fine in the case.

The AWDC did not have specific information on the amount of the fines. Judicial authorities in Antwerp could not immediately be reached for further comment on the case.

The HRD Antwerp grading bribery case dates back to March 2012, when news first surfaced that the lab fired a total of four graders for what it called at that time an “unprofessional act.”

That June, a total of four people--reported to be two diamond traders, an HRD employee and a “facilitator”--were arrested in connection with the case.

The AWDC said there is another firm allegedly involved in the case and that the public prosecutor in Antwerp is submitting an appeal to enable this firm to receive an “even heavier” sentence.

Antwerp acts with swift punishment, In stark contrast to the GIA, No action taken by GIA in their case.

HRD Antwerp corporate statement regarding the deliberate provision of incorrect diamond certificates by employees in 2012.

Last week, the Correctional Court of Antwerp delivered a verdict in  regards a case concerning the deliberate provision of incorrect diamond   certificates by employees in 2012. Following the verdict,  the Court    imposed severe sanctions on the involved parties including effective  incarceration, forfeiture of certain rights and substantial financial  penalties and compensations.  At the start of the process in 2012, HRD Antwerp and parent company   AWDC both have declared themselves civil party due to significant   reputational damage. Throughout this case, HRD Antwerp has had  full confidence in the investigation by the prosecutor's office but has  never been directly involved. The involved diamond companies and their representatives have  since been declared persona non grata and are no longer customers  at HRD Antwerp. The involved employees where immediately fired  due to severe professional errors. “HRD Antwerp fully supports the recent ruling of the Court in regards  this unfortunate case. It’s extremely important such violations do not  remain without consequences. The imposed sanctions are therefore  a strong signal towards the industry that such practices are not tolerated.  We like to thank our customers for their loyalty and confidence despite  this isolated case” says Peter Macken, CEO HRD Antwerp.

Record-Size Synthetic Diamond Grown

Unusual bluish orange luminescence is an identifying characteristic of HPHT–grown diamonds from NDT Russia, which has recently grown record-size synthetic diamonds.

A 60-carat high pressure-high temperature (HPHT)–grown diamond set a record for the largest laboratory-grown diamond crystal when it was formed the first week of July 2015 at the New Diamond Technology (NDT) facility in St. Petersburg, Russia. Branko Deljanin, senior gemologist at CGL-GRS, Vancouver, Canada, was visiting at the time and had a chance to examine the synthetic diamond. In April 2015, NDT had experimentally produced a 32.26-carat colorless, high-quality diamond crystal. From this stone, the largest laboratory-grown faceted diamond in the world has been cut. It is a 10.02-carat faceted square emerald-cut synthetic diamond (see Slideshow). NDT has been using the latest Chinese manufactured 850 series cubic presses, which are the biggest cubic presses on the market. As a result, many large stones can be produced in one run. Up to 16 colorless crystals weighing 6 carats to 10 carats can be made in a cycle that takes 10 to 12 days on average. The NDT facility in St. Petersburg has over 50 HPHT presses, including “TOROID”- and “CUBIC”- type presses, which produce 5,000 carats of diamonds per month. NDT built an in-house cutting facility, where the laboratory-grown diamonds are processed and polished.

                             

                             

                             

Synthetic Diamond History

   The first batch of industrial laboratory-grown diamonds were manufactured in 1953 by ASEA, a Swedish company, but this accomplishment went unannounced and mostly unnoticed. In 1970, General Electric (GE) produced high-quality synthetic diamond crystals using the HPHT method with a belt-type of press that created a .78-carat polished round brilliant colorless synthetic diamond. In the 1980s and 1990s, Russian scientists used their own technology “BARS” and “TOROID” high-pressure apparatus to grow industrial and gem-quality crystals up to 2 carats in polished size and mostly orange to yellow in color. In the past 15 years, companies including Lucent, Chatham, AOTC and Gemesis — now IIa Technologies — and many other producers in China, Germany, India, Russia, Ukraine, U.S. and Taiwan have improved the technology yet again and used their expertise to successfully grow diamond crystals that result in polished stones from 1 carat up to 2 carats in size. This “next generation” of diamonds exhibits high clarities — VS and VVS — and colors D through H, as well as new blue and pink colors that occur after irradiation. Other companies, including Scio Diamonds, Washington Diamonds, Taidiam, PDC Diamonds and Pure Grown Diamonds — the selling arm of IIa Technologies — are also using a very different technology/process known as Chemical Vapor Deposition (CVD) to produce laboratory-grown diamonds up to 3 carats in size, of similar quality compared to HPHT-grown diamonds.

 

Testing and Identification

   Mikko Åström, gemologist and co-founder of M&A Gemological Instruments, Finland, and Deljanin tested six of the largest crystals and polished colorless synthetic diamonds from NDT at the M&A Gemological Instruments facility. Three of the diamonds tested were the record-breaking 10.02-carat E, VS1; a 5.11-carat I, SI1 diamond and a 4.30-carat D, VS2 diamond. Six other samples — including two blue laboratory-grown diamonds — were tested at the GRS laboratory in Hong Kong by Matthias Alessandri, gemologist and advanced instruments operator at GRS Lab (Hong Kong) Limited, China, and Adolf Peretti, founder and chief executive officer (CEO) of GRS Gemresearch Swisslab AG, Switzerland. Both examinations used standard instruments and advanced spectrometers.

 

UV Fluorescence and Phosphorescence

   As found with other HPHT-grown diamonds on the market, the fluorescence of NDT-grown diamonds with short-wave ultraviolet (SWUV 254 nm) were greenish blue and more intense than with long-wave ultraviolet (LWUV 365 nm). This characteristic was observed in half the samples. Almost 90 percent of natural diamonds usually show some blue reaction under UV light and, in contrast to synthetics, fluoresce more intensely to LWUV than to SWUV. No natural diamonds, but most synthetic diamonds have more intense fluorescence under SWUV than LWUV light.

   An interesting new feature discovered in approximately half the samples, which were from NDT’s latest production in 2015, is a weak-medium bluish orange fluorescence and phosphorescence under an SWUV lamp (see Slideshow). This phenomenon was also present when the samples were exposed to a strong LED white light.

   All colorless laboratory-grown diamonds tested were type IIa with no presence of nitrogen and a small amount of boron. The blue laboratory-grown diamonds (see Slideshow) were type IIb, containing boron — responsible for the blue color — in higher concentrations than found in natural type IIb blue diamonds. Grayish blue CVD-grown diamonds could be either type IIb or IIa.

   Most NDT-grown diamonds studied exhibit high to medium clarity — VVS1to SI1. Based on this clarity, it is not possible to distinguish the majority of samples from similar-quality natural diamonds by using just a loupe or microscope. Only a few lower-clarity stones — especially unpolished — had metallic inclusions that are typical for HPHT-grown diamonds.

 

Strain Patterns

   Diamond is an isotropic material, which means that it exhibits the same properties in all directions, but it has anomalous double refraction (ADR) resulting from “strain” which is visible as a rainbow effect pattern under cross-polarized filters (CPF) (see Slideshow). One cause of strain in natural diamonds is the internal deformation of the crystal structure caused by heat and pressure from geological processes. As a result of the strain, a single light source is reflected in two directions within the diamond. Diamond cutters are aware of strain in natural diamonds and are very careful when cutting diamonds exhibiting high strain because they could break under heat/pressure produced while cutting. Strain patterns are visible under CPF.

Testing Technique

   Using the filter technique, a diamond may be tested by positioning it between CPF or in a portable polariscope and rotating the diamond while observing patterns in transmitted light with a loupe or microscope.

   Diamonds of different type and origin have different strain patterns under CPF:

    Low-nitrogen natural diamonds — type IIa — often have a typical “tatami pattern,” which are fine intersecting parallel dislocations.

    Natural diamonds that contain nitrogen — type Ia, comprising 95 percent of natural diamonds — have a strong strain pattern showing a multicolor rainbow effect.

    Synthetic diamonds grown by the HPHT method are not subjected to strong geological forces and so these synthetic stones are free of strain. An absence of any strain pattern under CPF is confirmation of synthetic origin. In the case of NDT, these are type IIa colorless or type IIb blue diamond grown using HPHT methods.

Practical Tips

   When examining a diamond for origin, it is important to use standard instruments such as a microscope with CPF or a portable polariscope and a UV lamp. The presence or absence of strain patterns is an indication of the diamond origin. They are present in natural diamonds, but absent in HPHT-grown diamonds. It is also necessary to check for the presence of blue fluorescence, a property of 90 percent of natural diamonds, or the absence of blue fluorescence, which is a characteristic of all synthetic diamonds and 10 percent of natural diamonds when viewed under an LWUV lamp. Additional testing at a gem lab will confirm the nature of the diamond.

Presence of Nitrogen

   Defect centers comprising nitrogen-vacancies (NV) like NV0 (575 nm) and NV- (637 nm) and silicon-vacancies Si-V- (737 nm) are present in approximately half the NDT samples. Si-V defects are found in CVD-grown diamonds and are very, very rare in natural diamonds. Nickel was not detected in the samples and if present, probably has a low concentration below the sensitivity of the photoluminescence (PL) spectrometers used at GRS and at M&A Gemological Instruments.

   In the opinion of the authors, orange color luminescence is most probably from NV centers, maybe in combination with other defects. This is most likely a characteristic of very large stones resulting from the long-lasting growth period when stones were exposed to high pressures and high temperatures.

Summary

   Diamonds grown by NDT are the largest colorless synthetic diamonds reported to date, with weights up to 60-carat crystals and 10-carat polished.

   Most samples are high color — D to I range — and high to medium clarity, but may contain metallic inclusions formed from metal/catalyst melt. Natural and CVD synthetic diamonds show strong Ia or weak IIa strain pattern as they are more heavily strained than HPHT synthetic diamonds from NDT, which do not show strain pattern under CPF. Colorless samples were type IIa with some boron — weak type IIb — or blue with high boron content, so it is possible to distinguish them from natural stones of similar color. All samples fluoresced and phosphoresced blue and half of them orange when exposed to a UV lamp, with stronger responses to short-wave than long-wave excitation and lasting phosphorescence. Natural diamonds show a stronger reaction — usually blue — under LWUV than SWUV light. Only rare chameleon and type IIb natural diamonds phosphoresce, but not with a blue/orange color, but yellow for chameleon and red for blue diamonds.

   Photoluminescence spectra revealed NV centers, which in combination with other defects could be responsible for orange luminescence. Boron impurities are responsible for the blue phosphorescence in HPHT-grown diamonds but the exact nature of orange phosphorescence is still not fully understood, and further research is underway at GRS and CGL-GRS labs to also understand the role of boron and other impurities present.

   Using a combination of standard gemological and spectroscopic tests, it is possible to identify all NDT colorless and blue HPHT-grown diamonds and thereby distinguish them from natural diamonds of similar quality.

   The authors predict that in the future large-sized HPHT-grown pink diamonds will be produced using Beta irradiation in combination with high temperature treatment from type Ib yellow starting material, similar to the process reported (“Contributions to Gemology” No. 14, pages 21 to 40) to obtain the pink color in CVD-grown diamonds.

   Deljanin has had the opportunity to study HPHT-grown and CVD-grown samples from all producers of synthetic diamonds that openly sell to the jewelry industry in the past 15 years and this is the first time that HPHT-grown diamonds are exhibiting an orange luminescence, which is usually a characteristic of CVD-grown colorless diamonds under SWUV light. The most surprising phenomena is that even visible pinpoint light triggers this orange reaction, indicating that it could be a straightforward and simple “screening test” for most larger synthetic diamonds coming from NDT, Russia.

About the Authors

   Branko Deljanin is president and senior gemologist at CGL-GRS, Vancouver (Canada), info@cglworld.ca. Matthias Alessandri is gemologist and operator of advanced instruments at GRS Lab (Hong Kong) Limited, Hong Kong (China). Dr. Adolf Peretti is founder and CEO of GRS laboratories in Switzerland, Hong Kong, Thailand and Sri Lanka and partner of CGL-GRS in Canada. Mikko Åström is gemologist and co-founder of M&A Gemological Instruments (MAGI), Järvenpää (Finland). Dr. Andrey Katrusha is consultant and scientific adviser to NDT, St. Petersburg, Russia.

Source: diamonds.net