GGTL Laboratories is the merging of two laboratories: GemTechLab, founded in 1996 by Franck Notari in Geneva, Switzerland and GEMLAB (Liechtenstein), founded in 1996 by Thomas Hainschwang in Balzers, Liechtenstein.Our Swiss laboratory is located in western Switzerland in the French speaking city of Geneva, the Swiss capital of watches, gems and jewellery. Geneva borders France and is the most international city of Switzerland. At the GGTL Switzerland Laboratory all gem testing services are provided and this site is the only site of GGTL where emerald cleaning and re-oiling services are performed; with this service in place for seventeen years, emerald treatment and origin testing is one of the specializations of the laboratory. Being in the middle of the Swiss watchmaking industry, another major specialization of GGTL Switzerland is the quality analysis of melee-sized colourless (D – Z) diamonds, including the screening for synthetic diamonds and imitations in such parcels. With a very talented diamond cutter in the building, all diamond re-cutting services, for D-Z and fancy coloured diamonds are offered at the Swiss laboratory.Franck Notari is lecturer at the University of Nantes since more than ten years; for this reason, the Swiss laboratory is also involved in the training of students for the University Diploma of Gemmology (DUG), amongst others by offering them a one-year internship at the laboratory to prepare for the submission of their diploma work.