Gemmological examinations of historical jewelry

Speaker: Dr. Tom Stephan (DGEMG, Germany) & Dr. Ulrich Henn (DGEMG, Germany) Dr. Tom Stephan studied geosciences at Johannes Gutenberg University in Mainz. Alongside his studies, he has worked since 2014 as a research associate and seminar facilitator for the German Gemmological Association in Idar-Oberstein and is now vice-director. Since 2016 and as part of his doctorate (completed in 2020), he has also dealt with color examinations and calculations of gemstones colored by Cr3+ and/or V3+ such as rubies and emeralds. Tom Stephan regularly publishes articles in various national and international gemmological journals and he presents the results of his research at gemmological conferences such as the International Gemmological Conference (IGC) and the European Gemmological Symposium (EGS). ************************************* Dr. Ulrich Henn studied mineralogy and gemmology at the Institute for Gemstone Research at the University of Mainz, where he also obtained his doctorate. He is managing director of the German Gemmological Association, head of the DGemG training center and a member of the board of the German Gemstone Research Foundation. Dr. Henn is a member of the Gemmological Association of Great Britain (FGA) and a representative of the International Gemmological Conference (IGC). From 2006 to 2011, he also served as Chairman of the Federation of European Education in Gemmology (FEEG). He is the author of several books on gemstones and numerous articles in internati