Last week at the Kimberley Process Intersessional meeting in Antwerp, during the Special Forum, "Innovation and Technology: State-of-the-art in the rough diamond trade", Daniel Nyfeler, Managing Director at Gübelin Gem Lab gave a presentation on the company's 'Emerald Paternity Test'. As a component of Gübelin Gem Lab's Provenance Proof initiative, focused on developing new technologies to increase transparency and traceability within the gemstone industry, the Paternity Test - now being applied in full by Gemfields - utilizes cutting-edge tracer technology to tag various materials with information about its origin. We were curious to know the extent to which this groundbreaking traceability tech is applicable to diamonds, and sought out Mr. Nyfeler after the meeting.
To explain the technology (in layman's terms), in the case of the Emerald Paternity Test, Gübelin has customized DNA-based, nano-sized particles to become a source of encrypted information about the mining location, the miner and date mined, stored within the stone itself. They place this information into the DNA structure of nanoparticles, which are themselves placed into a carrier liquid into which rough emeralds are submerged. The liquid containing the nanoparticles penetrates the fissures in the emerald, enabling the nanoparticles to adhere closely to the internal surfaces of the fissure walls; they can be retrieved and decoded at a later stage, disclosing the paternity of the emerald. Importantly, sufficient DNA tags remain in the fissures during cutting, polishing and re-oiling processes, so it is usually possible to determine their origin at a later date. Is this also the case for diamonds? Also, this seems (to us) like a highly complex and expensive process: Daniel Nyfeler explains.
(Relatively) affordable science-fiction
The Gübelin Gem Lab, explains Nyfeler, discovered this type of nanoparticles and decided to start the research needed to customize the technology to be applied on gemstones, starting with emerald, and in 2016 needed more material "to play with". Among the miners they contacted, Gemfields answered the call, and are now using the technology at scale. When we pointed out it seems like a costly technology, Nyfeler told us, "Though it is likely too much of a stretch for truly artisanal production, as the costs per gram of rough is typically too high, it is actually affordable even for small-scale miners, perhaps as a collective, or through a government that wishes to guarantee the provenance of the resources produced in their country in order to earn higher prices for them. The lowest price for a small-value annual package is about $50,000. For large-scale applications, applied frequently annual costs can go up to $500,000, all of which varies according to the size of the parcels and frequency of testing. And there is a trade-off between the level of certainty and cost. If you are tagging stones in the pit itself, you have 100 percent security of origin, but it becomes costly to send someone to every small mine and set up a multitude of service packages, which also adds to the cost. There is also the option of tagging the goods at the export stage, which is not 100% secure, as batches could be mixed before that stage, but is much more feasible in terms of cost. However, a ‘bag & tag’ system could help mitigate the risk of mixing between the mine and the actual tagging location."
He explained that the tagging process itself is actually rather low-tech (just the carrier liquid, containers, an agitator to stir the mixture and controller) and can be done anywhere by (almost) anyone, though the application of the tracer technology in the mine is handled exclusively by either Gübelin Gem Lab or UL, an independent, professional auditor. At this point, clients wishing to have the Paternity Test carried out must send the stone(s) back to one of Gübelin's labs, which has the proprietary knowledge to retrieve it. However, Nyfeler says, "It will be easy" to decentralize the process. "We just have to share the recipe", contracting a few other laboratories to extract the nanoparticles. The decoding of the information stored in the nanoparticles remains exclusively with the Gübelin Gem Lab, and can be done via a web interface.
Diamond Paternity Test?
The main issue we wanted to know, of course, is whether it would work for diamonds. "Emeralds have natural openings, microscopic and even submicroscopic openings. Even after cutting, it will still have the DNA information in its fissures. With diamonds, however, our current assumption is that the information does not survive the cutting and polishing process. The cleaning process for diamonds, deep boiling in acid, also harms the nanoparticles. What we have confirmed, however, is that it does work for the first part of the pipeline, from mine to polishing wheel, provided the tagging takes place after any deep-boil cleaning process has occurred. The lab-phase of our technical feasibility study has succeeded in retrieving the particles and thus tracking diamonds as rough."
While Gübelin's Paternity Test is thus not the 'holy grail' of tracking diamonds from mine to finger, it does provide a new option to, for instance, the Kimberley Process, when it needs to verify the origin of rough diamonds. Say a particular area - like the Central African Republic today - has a real need for verification of the exact mine from which a particular diamond was recovered, this technology could provide it rather easily. Additionally, as Nyfeler told us regarding the added value of the Paternity Test, "We believe having some kind of physical tracer makes the Blockchain so much more robust than with the Blockchain alone. Blockchain technology ensures the security and integrity of data, but it cannot determine if the stone it references is the real stone. Adding a physical tracer linked to the Blockchain means the stone cannot be swapped out unnoticed. When information on nanoparticles is registered on the blockchain, one has the option to actually test if there has been any change."
But a retailer with a demanding customer cannot send a polished diamond back to a Gübelin lab, or anywhere else for that matter, to have its origin verified physically. "It has never been possible for a gem lab to physically determine the origin of a diamond with 100% certainty just by examining the mineralogical structure of a stone. Colored gemstones, on the other hand, show a wider variety of origin-specific properties that enable determination of origin. But with diamonds, it is actually a geological problem, as diamonds are created in the earth’s mantle and are often carried great distances over the course of millions of years. Now, with the nanoparticles, we have found a way to not only determine the country of origin, but also the exact mine, albeit only from the mine to the cutting wheel. Nevertheless," Nyfeler adds, “this is a great leap forward.” Stay tuned.