Characterization of the incuse coins of the Museo Campano in Capua (Southern Italy) by X-ray fluorescence and numismatic analysis

•X-ray technique and numismatic analysis are combined for the study of the Incuse coins of Magna Grecia.•Numismatic analysis provides the synoptic distribution of the samples and the historical period.•XRF analysis and multivariate data characterize, classify coins and provide further information.•Indications on production processes, origin of materials and historical changes in the coinage.•X-ray imaging is applied to highlight the surface enrichment of silver. X-ray fluorescence and numismatic analyses have been used for the study of a sample of incuse coins at the Museo Campano (Capua, Italy). A group of 31 silver incuse coins (staters and drachmas) of the first coinage (530 BCE to 470/440 BCE) iussed by four cities from southern Italy has been characterized. Numismatic examinations provided indications on the synoptic distribution of the specimens from the different colonies and on the historical period. XRF and multivariate data analyses characterized the coins and provided additional information. Results show that the examined coins consist of a silver-copper alloy (with Ag > 95%). Trace elements indicate that the alloy may come from the same mine. Values of the AgKα/Lα intensity ratio and Ag-Cu alloy standards allowed to identify some surface enriched coins. Other characteristics implied evidence that three coins of Metapontum and Croton could be overstruck.