Advances in Gemstone Traceability Technology

29/03/2017 10:15

Gübelin Gem Lab introduced the “Emerald Paternity Test”, a technology developed for tracing the origin of emeralds to their exact mine. They were able to do this by using nanotechnology to mark stones with an invisible imprint that is accessible at any stage of the supply chain. The technology is a “true game-changer for the colored-gemstone industry,” said the Switzerland-based laboratory.

The mining location, the miner and the mining period are encrypted and stored in the DNA, which through invisible tagging of nanoparticles are imbedded on the rough emerald. The encryption is encapsulated in a sphere of amorphous silica, an ethanol-based liquid, which is designed to resist the influence of cleaning, cutting, polishing, transportation and setting. The emeralds can be decoded at any point in their journey from mine to jewelry to disclose their paternity.

According to the lab, this customized process is the first time nanotechnology – the branch of technology dealing with dimensions smaller than 100 nanometers – has been used for the specific needs of the gemstone industry. The nano-particles are small enough not to impact the appearance of the stone, even with an optical microscope, meaning they will not affect a stone’s grading properties. “This technology offers all stakeholders along the entire supply chain, from the miner to the final customers, proof of the exact source of emeralds, instilling confidence and creating trust,” said Daniel Nyfeler, Gübelin Gem Lab managing director. “It enables a new level of transparency for the gemstone trade.” The right to using the technology is subject to a Code of Conduct, defining the use and application of the technology.

Such technology will likely be adopted throughout the gemstone industry in order to prevent challenges such the one the Swiss Gemological Institute SSEF is currently facing. The Institute has analyzed a large number of sapphires from a new deposit near Bemainty/Ambatondrazaka in Madagascar that have a 'Kashmir-like' visual appearance. These are characterized by a subtle and fine milkiness, resulting in a velvety blue appearance, typical of top-quality Kashmir sapphires. The SSEF believes careful microscopic observations combined with advanced methods of trace element detection such as GemTOF or Raman microspectrometry, are methods of distinguishing the origin of these sapphires. Should their origin not be correctly disclosed, the trade could face considerable financial and reputational setbacks.