The 29th issue of Facette, the annual gemological magazine published by the SSEF, the Swiss Gemmological Institute, has been published in 2024. This issue contains articles and research that explore the latest developments in the world of gemstones and pearls. One such article is by Dr Michael S. Krzemnicki, entitled “Unravelling the Secrets of Antique Jewellery”. Using tests conducted on antique jewellery at the SSEF, this study highlights the use of imitation emeralds and the reuse of gemstones in new settings, providing valuable insights into historical alterations and craftsmanship.
Another intriguing paper by Dr Krzemnicki focuses on the analysis of a 2.10 carat ruby from Vietnam. This vibrant red gem was classified as “pigeon’s blood red” according to SSEF’s strict standards. While most rubies in this category typically come from Burma, the Swiss institute has identified specimens from other regions, including Vietnam, Tajikistan and East Africa. The classification is based on colour, absence of treatments and strong fluorescence under UV light, without taking geographical origin into account.
The article “Effects of Gamma Irradiation on Ruby and Pink Sapphire: An Update” by Dr Hao Wang explores the use of irradiation to alter and enhance gemstone colour. This treatment, which uses gamma rays to create colour centres in the crystal structure, can result in significant colour changes, particularly in rubies and sapphires. The SSEF, in collaboration with the Swiss Centre for Radiosurgery, is conducting experiments to better understand the effects of this treatment and to develop methods for detecting it, stressing that there is still no universal standard for identifying it without pre-treatment analysis.
The magazine also features in-depth articles on Paraiba tourmalines, Afghan spinels and chrysoberyl. All these articles and more are available at www.ssef.ch/research-library/.
