Scientists recovered minute amounts of DNA from a wide range of pearls. Image courtesy: Swiss Gemmological Institute.
Scientists achieve pearl breakthrough
Posted November 11, 2013 | By Emily Mobbs • Former Editor
Scientists in Switzerland are said to have achieved a breakthrough in
pearl research, whereby the origins of pearls can now be traced using
oyster DNA.
Researchers at the Swiss Gemmological Institute (SSEF), in collaboration with the Swiss Federal Institute of Technology Zurich (ETHZ), say they have mastered the extraction of oyster DNA from pearls, allowing them to trace and identify the pearl to their specific origins.
Scientists were able to recover minute amounts of DNA from a wide range of pearls that came from Pinctada maxima, Pinctada margaritifera and Akoya oysters as well as Pinctada radiata from the Arabian/Persian Gulf, Pinctada maxima from Australia and Indonesia and Pinctada margaritifera from Fiji and French Polynesia.
An important part of the two-year project was reportedly the development of a practically non-destructive technique to extract DNA in order to preserve the commercial value of tested historic and modern pearls. In one sample, 10 mg of drilled sample powder was sufficient to successfully identify the pearl oyster species based on extracted DNA material.
Read more: Pearls explained
Commenting on the research, SSEF director Dr Michael Krzemnicki said: "These new methods give us a considerable advantage in distinguishing different types of pearls and for the future documentation of historic pearls. We hope to add them as client services in the near future."
The researchers' results have just been published in the international open-access journal PLoS ONE, and the technology is currently being patented. The findings build upon another pearl research project conducted by SSEF to determine the age of pearls.
Both DNA “fingerprinting” and age determination are said to improve traceability in the pearl industry and offer a new way to document the provenance of natural and cultured pearls.
Impact on local industry
Managing director of Adelaide-based retail store Raw Pearls, Dr Dyann Smith, said it was refreshing to see these methods being put to use in an industry that rarely used scientific knowledge to identify, let alone age date, a pearl.
“In spite of what some non-gemmologist jewellers believe, an ‘educated eyeball’ and the gritty feel of nacre on teeth [due to overlapping platelets of nacre covering the external surface of a pearl] will not discriminate natural from cultured pearls,” Smith explained.
“Therefore the industry should feel very encouraged by this exciting research as it will assist the industry greatly in both areas of identification and provenance of origin and location with different pearl species,” she added.
Furthermore, she said that being able to identify a certain species of oyster and its provenance would increase the value of specific pearls.
GAA federal publicity and marketing officer Kathryn Wyatt believed that while the findings would not presently have a large impact on the jewellery industry, it might be useful in the future to help identify freshwater pearls, which are increasingly improving in quality and size.
Background reading
Freshwater Pearls – the facts
Pearl types
Cultured pearls – the facts