Multi-analytical characterization and provenance identification of protohistoric metallic artefacts from Picentia-Pontecagnano and the Sarno valley sites, Campania, Italy

Protohistoric metal objects coming from the archaeological sites of Pontecagnano (Salerno, Italy) and Striano (Naples, Italy), preserved in the Pontecagnano National Archaeological Museum and the Paleontological Museum of Naples University “Federico II” have been studied by means of an archaeometric approach. A multi-analytical procedure including X-ray powder diffraction (XRPD), scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDS), micro X-ray fluorescence (µ-XRF) and lead isotope ratio mass spectrometry (LIRMS), was used to characterize these objects thus providing hypotheses on the possible provenance of metallic raw materials. The investigated samples are represented by lead, silver, copper and tin bronze-based objects. Corrosion processes affecting the bronze objects were recognized as well as crusts and patinae at different stages of evolution. LIRMS analyses suggested that most of Pontecagnano artifacts were manufactured with metals from southern Tuscany, where important metal reserves were located. On the other hand, due to the limited number of samples, the provenance of the Striano objects cannot be unambiguously identified although data so far available suggest a Sardinian source.