Dr. Michael S. Krzemnicki, FGA – Director of SSEF

Michael has been with SSEF since February 1998. Following his tenure as director of education, he became director of the SSEF laboratory in June 2009. He is involved in gemstone testing, education, and management of the laboratory. Dr Krzemnicki holds a Master’s degree in Mineralogy and received his PhD in 1996 from Basel University (Switzerland). He received his FGA Diploma in January 1998. For many years he has been lecturing in gemmology at the University of Basel, where he is a Privatdozent (PD). He is a fellow of the Gemmological Association of Great Britain and member of the scientific board of the Swiss Gemmological Society SGG. He is also on the executive committee of the International Gemmological Conference (IGC). A selection of his publications can be found here. He is assisted in his management duties by Victoria.

Gemmological Department

Pierre Lefèvre, MSc, DUG – Head of Gem Testing

Pierre joined SSEF as a gemmologist in August 2005 and is head of gemstone testing at SSEF. He holds a Master’s in mineralogy from Liège University in Belgium, having completed his studies in 2003. In parallel, he followed courses at the “Société Belge de Gemmologie” in Brussels, and received the FEEG Diploma (Federation of European Education in Gemmology) in 2003. In 2005 he completed his studies on gemstone treatments with a DUG Diploma (Diplome Universitaire de Gemmologie à Nantes, France). From 2003 to 2005, he was lecture assistant at the University of Liège, Belgium.

Dr. Wei Zhou, FGA

Wei joined SSEF as a gemmologist in April 2011. She holds a Bachelor in gemmology from the China University of Geosciences (Beijing) and a Master in mineralogy from the same institution. She completed her PhD in 2011 at the Institute of Mineralogy and Geochemistry at the University of Freiburg in Germany. She completed her FGA Diploma in 2013.

Alexander Klumb, MSc, FGA

Alexander joined SSEF in 2011. He has a Bachelor in Geosciences from the University of Basel and a Master in Geosciences from the same university, and recently obtained his FGA diploma. He works for SSEF as a gemmologist.

Dr. Tashia Dzikowski, FGA

Tashia joined SSEF in February 2014, and is currently working as a gemmologist. She completed her Bachelor of Science in Geological Sciences at the University of Manitoba (Winnipeg, Canada), followed by both her Master of Science (MSc) and PhD in Geological Sciences at the University of British Columbia (Vancouver, Canada). Her PhD research was on the origin of ruby and sapphire in marble from two different localities in Canada. During her PhD, she was also a lecturer at the University of British Columbia where she taught an introductory course called Gold and Gems. She completed her FGA diploma whilst at SSEF and today works as a gemmologist for SSEF.

Chiara Parenzan, MSc, GG

Chiara first joined SSEF in 2007, and then again in 2018 as a gemmologist. She took her G.G. in 2004 and completed her M.Sc. in Mineralogy from the University of Bologna (Italy) with a thesis in petrography in 2006.

Michael Rytz, MSc

Michael Rytz has been with SSEF since 2015 and is working as a gemmologist. He completed his MSc thesis at the University of Basel on chrysoberyl from different deposits.

Dr. Laurent E. Cartier, FGA

Laurent joined SSEF in 2010 and is Head of Education at SSEF. He holds a Masters in Earth Sciences from Basel University and completed his FGA Diploma in 2008. He holds a PhD from Basel University that focused on pearl farming and pearl traceability issues. He is a lecturer for Gemmology at the University of Lausanne (UNIL) and an affiliated associate professor at the University of Delaware (USA). He is a co-founder of the Sustainable Pearls project and also a co-founder of the Gemstones & Sustainable Development Knowledge Hub. He is actively involved in the Swiss Gemmological Society (SGG) and the International Gemmological Conference (IGC). He is involved in different project management, research, and teaching activities at the SSEF. A selection of his publications can be found here.

Diamond Department

Jean-Pierre Chalain, DUG – Head of Diamond Department & Deputy Director SSEF

Jean-Pierre has been with SSEF since July 1994 and is currently director of the diamond department. He completed his Diploma of Gemmology at the University of Nantes in 1992. His main working fields in the laboratory are colourless and coloured diamonds, but he is also involved with the testing of coloured stones and pearls. Jean-Pierre is a delegate of Switzerland at the World Jewellery Confederation (CIBJO).

Luc Phan

Luc has been with SSEF since June 2006. He works on quality assessment of small diamonds and grading of large diamonds, and as a photographer of gemstones and jewellery items.

Ly Phan

Ly joined SSEF in 2013. He works on quality assessment of small diamonds and grading of large diamonds. He is also an ASDI instrument specialist.

Julien Xaysongkham

Julien has been with SSEF since March 2008. He is a specialist in the quality control of small diamonds and grading of large diamonds. He is also involved in the teaching of diamond courses at SSEF.

Dr. Laura Speich

Laura joined the diamond department at SSEF in September 2019. She holds Bachelor and Master of Science degrees in Geosciences from Ruhr-University Bochum (Germany). During her PhD in geology at the University of Bristol (United Kingdom), which she completed in 2017, she focused on platelet defects in diamond and their application as a mantle thermometer.

Analytical Department

Judith Braun – Head of Analytics

Judith joined SSEF as an analytical scientist in 2012. She previously worked as a laboratory head at UMICORE and as a specialist for ICP and X-ray techniques. She now does pearl radiographies and micro X-ray computerised tomography for pearls at SSEF. She also operates instruments such as ED-XRF, UV-Vis, FTIR, Raman microspectrometry, and GemTOF. She provides gemmologists the chemical and spectral results they require for the identification of gemstones. She is joined by Gina, Hannah, Ramon, and Susanne in the Analytical department.

Dr. Hao Wang

Hao joined SSEF in autumn 2015 and is now working as a research scientist. He obtained his PhD at ETH Zurich in 2013 developing LA-ICP-MS methods. Currently, Hao is mainly responsible for GemTOF – a state-of-the-art LA-ICP-Time Of Flight-MS platform at SSEF, data management and statistics.


Alexandra Kokkinopulos – Head of Administration

Alexandra is head of administration, joining SSEF in 2011. She has a degree in business administration and previously worked for several companies in the Basel region. She is responsible for accounting, client contacts and general administration. She works with Özlem, Tania and Véronique in the administration team.

Photo Department

The photo department at SSEF ensures that high-quality photos of items submitted to SSEF are taken. This includes photo editing techniques and the production of SSEF reports and imagery for Premium Appendices.

Production Department

Thomas Gohl

Thomas is responsible for the production of reports at SSEF. This includes preparation of SSEF’s reports, quality control and activating validation features (such as Prooftag and MySSEF) of reports. He is assisted in his work by Matej.


Michael Schmitt – Head of IT

Michael joined SSEF in 2019 and heads our IT. He is assisted in IT by Eli.

Research associates

Prof. Dr. Henry A. Hänni, FGA

Prof. Dr. Henry A. Hänni is a senior research associate with SSEF. He was the director of SSEF from 1990-2009. He received his doctorate in Mineralogy from the University of Basel in 1980 and earned the title of professor in 1996 from the same university. He received his FGA Diploma in 1978. He has been regularly teaching gemmology courses at Basel and Lausanne universities for three decades. Prof. Hänni has published over 150 articles on gemstones and analytical techniques in numerous journals.

Dr. Walter A. Balmer, G.G., MBA

Walter obtained his M.Sc., in Earth Sciences from the Swiss Federal Institute of Technology (ETH) in Zurich with a major in Petrology-Mineralogy and Geophysics in May 2001. He completed his Graduate Gemologist studies at GIA Carlsbad the same year. In December 2011, he completed his Ph.D. studies on the “Genesis and Trace Element Composition of Rubies from Marble-Hosted Deposits in Morogoro, Tanzania”, at Chulalongkorn University’s Department of Geology in Bangkok. From 2002 until 2005 he was a senior staff gemologist in the Gubelin Gem Laboratory in Luzern. Post-Gubelin, Walter focused on lecturing at both Kasetsart University and at the Gem & Jewelry Institute of Thailand (GIT), the latter in his role as a research consultant. He has widely published and presented research in gemmological journals and at conferences worldwide.

Dr. Bertalan Lendvay

Bertalan is a research associate with SSEF. He holds an MSc in Biology and a Ph.D. in Horticultural Sciences. He has worked on genetic analysis of low copy number DNA samples originating from subfossil plant remains, tropical wood, and herbarium specimens at the Hungarian Academy of Sciences, the Swiss Federal Institute of Technology in Zurich (ETHZ) and the Swiss Federal Institute of Forest, Snow, and Landscape Research (WSL). At the forensic genetics research group of the Institute of Legal Medicine at the University of Zurich, his aim is to develop and validate quasi non-destructive genetic analysis methods to determine the species identity of pearls and corals processed for jewelry. These methods will be novel tools to enhance traceability and ultimately the conservation of vulnerable and valuable marine resources.

Dr. Joana B. Meyer

Joana is a research associate with SSEF. She holds a Biology Masters from Lausanne University and a PhD from ETH Zurich where she researched soil microorganisms and plant-bacterial interactions. She is an expert in DNA fingerprinting techniques in a range of materials and organisms.