Our research has started in October 2015, with specific metallographic analysis performed on a first selection of numismatic findings. A second step of analysis will detect the specific isotopes of the metals used in coin production.

The selected coins are made of silver or “mistura” (silver and copper) and come from archaeological excavations undertaken in the Colline Metallifere district. They cover a chronological range that goes from 10th to 13th centuries.

Between December 2015 and January 2016, a further selection of 40 coins, based on the criteria of chronology, type and metal, was analyzed through pXRF analysis. These pieces come from the archaeological sites of Donoratico, Miranduolo, Rocchette Pannocchieschi, Montemassi, Monteverdi, Canonica di San Niccolò (Montieri), Poggibonsi and Pava (San Giovanni d’Asso). Among the 40 specimens, 15 are silver coins while the others are made of  “mistura” (alloy of copper and silver). The pXRF analysis allowed to detect the amount of silver in the alloy, and has been used to optimize the further metallographic analysis.