CERSA Gems

CERSA Gems

CERSA Gems is the commercial arm of the Department of Earth Sciences dedicated to the physical characterisation of precious minerals. The gems industry relies on the trust of the consumer that the products it delivers are indeed as they are described. This integrity is being threatened on three separate fronts: a) whether the material is natural or synthetic, b) the source of the material (as the locality can significantly affect value) and c) disclosure of treatments used to improve the material. Due to recent advances in technology, all of these areas are under a constant threat fuelled by enormous profits that are generated by passing off a low value natural or synthetic product as a rare high value product.

 

The industry attempts to counter these threats using traditional gemmological techniques and, when these are inadequate, have utilised ever more sophisticated scientific analysis techniques.  At St Andrews we are addressing these issues through the research and development of testing techniques utilising our expertise in continuous and Time Resolved (TR) fluorescence techniques, an extremely sensitive and primarily non-destructive methodology of testing. The Department hosts some of the world’s most sophisticated analytical facilities designed and purpose-built for the characterisation of gems and minerals. These vary from traditional methods such as UV-Vis absorption to photoluminescence and beyond to bespoke advanced time-resolved x-ray luminescence methods as a function of temperature from 25 K to 400°C.

 

The group leader of CERSA Gems, Adrian Finch, has interests in mineral physics which have led to publications on the luminescence of minerals and the development of new luminescence methodologies. Characterising the physical properties of gems and relating them to composition and defect structures is behind much of the research the group undertakes that has application within both gemmology and mineralogy generally. The group also continues an active research programme using synchrotron light at the Diamond synchrotron facility [link to www.diamond.ac.uk] which complement in house research. Richard Taylor was the managing director of a number of commercial companies working within the gem and diamond industry prior to coming to St Andrews, including the UK’s largest Gem and diamond testing laboratory. That laboratory was unique as being the only commercial laboratory in the UK to have the expertise and equipment to identify both treated and synthetic diamonds.