1. Ghent University, Department of Chemistry, Atomic & Mass Spectrometry – A&MS Research Unit, Campus Sterre, Krijgslaan 281 – S12, 9000 Ghent, Belgium
2. Historical Archaeology Research Group, Department of Archaeology, Ghent University, St.-Pietersnieuwstraat 35, 9000 Ghent, Belgium
3. Centro de Investigación Mariña, Universidade de Vigo, Departamento de Química Analítica y Alimentaria, Grupo QA2, 36310 Vigo, Spain
4. Laboratory for Mineralogy and Petrology, Department of Geology, Ghent University, Krijgslaan 281-S8, 9000 Ghent, Belgium