Editor’s Note
This article explores how advanced analytical instruments like the GemTOF are revolutionizing gemstone research. By capturing comprehensive chemical data through laser ablation, these tools provide unprecedented insights into gem origins and authenticity, showcasing the growing role of technology in scientific fields.
In 2016, SSEF started using the groundbreaking GemTOF instrument in its facility, which conducts chemical analysis on gemstones through laser ablation—a process whereby tiny amounts of material are removed from the surface of a gemstone using a focused laser beam.
Like other laser ablation systems, it extracts chemical information from a few tiny laser-ablated pits. But unlike other systems, GemTOF can capture the presence of all elements simultaneously.
Such testing results in large amounts of trace element data that requires the use of statistical methods to find relevant patterns that can be used to help determine a gemstone’s origin.
To aid in analyzing the vast amounts of multi-dimensional data, about two years ago SSEF started using a non-linear machine learning algorithm, which can help identify relevant elemental similarities in the data sets, such as trace elements found in gemstones of different origins.
Gübelin Gem Lab, too, has taken steps to advance gemstone analysis through machine learning.
The lab announced in 2020 it was partnering with Swiss research and development center CSEM to develop a platform that will automate the process of determining gemstone authenticity and origin.
Together, Gübelin and CSEM will work to develop machine learning-based algorithms to evaluate standard gem characteristics using existing data sets as a base, i.e., the catalog of tens of thousands of client gemstones the lab has tested since the 1970s along with the Gübelin Reference Stone Collection comprising more than 27,000 gems.
Gübelin’s Provenance Proof initiative, launched in 2017, has moved the colored gemstone industry forward when it comes to improving traceability and transparency.
One of the lab’s key advancements was the “Emerald Paternity Test,” which involves applying DNA-based nanoparticles directly onto rough emerald crystals at mining sites.
The nanoparticles aren’t visible to the naked eye and can withstand all steps in the stone’s journey—cutting, cleaning, polishing, transporting, and setting—to act as a permanent tag supplying information on when, where, and by which company an emerald was mined.
Gübelin also introduced a blockchain for colored gemstones with the aim of following them through the supply chain from mine to market.
The Swiss gem lab first announced this development in 2018, partnering with mining company Fura Gems for the pilot program; the latter offered stones at its Coscuez Colombian emerald mine as test subjects for the blockchain.
The lab then opened the blockchain to the trade the following year, spinning it off from Gübelin Gem Lab by establishing it as an independent subsidiary under the House of Gübelin.
SSEF researched the radiocarbon dating of biogenic gems like pearls, coral, and ivory in collaboration with the Laboratory of Ion Beam Physics of the ETH Zurich, and started offering age-dating services to the whole industry beginning with pearls in early 2017.
To perform the radiocarbon analysis, the lab developed a quasi-non-destructive method of extracting a minute amount (approximately 0.02 carats) from a submitted pearl, coral, or ivory.
The lab can also age-date some colored gemstones when there is a suitable inclusion present near the surface, which it believes could support origin determination since gems from different sources formed during different geological periods.
SSEF also has led the research regarding DNA fingerprinting and species identification of biogenic gems for years, including pearls and, more recently, ivory and coral.
Studies done in partnership with the Institute of Forensic Medicine at the University of Zurich resulted in a patented method of species identification using minute amounts of DNA recovered from as little as 0.0115 carats of the pearl, ivory, or precious coral.