1. Department of Biological, Geological and Environmental Sciences, University of Catania, Catania, Italy
2. Institute of Geochemistry, Mineralogy and Mineral Resources, Charles University in Prague, Prague, Czech Republic
3. Department of Archaeology, Ghent University, Gent, Belgium
4. Department of Physics and Earth Sciences, University of Parma, Parma, Italy
5. Regional Museum Paolo Orsi, Siracusa, Italy