LAMQS, EDXRF and SEM analyses of old coins

Physical analyses by Laser Ablation coupled to Mass Quadrupole Spectrometry (LAMQS), Energy Dispersive X-Ray Fluorescence (EDXRF) induced by electron beam and SEM (Scanning Electron Microscopy) morphological nvestigations have been employed, as not destructive analyses, in order to characterize the surface of different old coins. Gold, silver and bronze coins have been studied to know their superficial patina composition and morphology. In particular LAMQS permitted to investigate the elemental, chemical compounds composition and isotopic ratios without damage the laser irradiated surface.The comparison of similar coins permitted to identify true and fake samples, so as demonstrated for different coins and for a rare silver tetradrachm Greek coins dated 480 - 461 B.C., which has many imitations.