Phd in EARTH SCIENCES

Thesis title: Bronzes between Sardinia and Etruria. Multi-analytical characterization and trade networks from the Late Bronze Age to the Late Iron Age

This PhD thesis concerns the study of archaeological bronze artifacts belonging to two Italic civilizations, the Nuragic (Sardinia) and the Etruscans (Central Italy), in the period from the Late Bronze Age to the Late Iron Age. Both civilizations were important for cultural and commercial centers, due to the emergence of long-distance trade routes, which facilitated the circulation of assets, technological knowledge, and cultural models. Sardinia was rich in copper, lead, and silver deposits, thus becoming a strategic region for trade, due to its central position in the Mediterranean basin, while Etruria, which evolved from the Villanovan culture, exploited local metal resources such as those of the Island of Elba and the “Metalliferous Hills”. Both civilizations, despite having abundant local resources, adopted economic strategies that involved importing, reusing, and remelting metals, highlighting an economy based on the circulation and exchange of ore materials. The existence of established contacts between the two populations during those centuries has been confirmed by various archaeological finds, which bear witness to exchanges of both finished objects and raw materials in both areas. The general objective of this research is to increase knowledge about the metallurgical skills possessed by the Nuragic and Etruscan peoples and to provide further evidence of the relationship between the two communities. This was achieved through a comparative study of artifacts belonging to both civilizations. The artifacts were selected and divided into three macro-categories, i.e., ornaments, statuettes, and tools/weapons, to include different contexts of metal use, such as social, sacred, and utilitarian. Within each category, different artifacts were selected, but they all shared a common functionality. The artifacts come from Sardinian museums and from Etruscan archaeological sites (Vulci, Bolsena, and Pyrgi). This thesis adopts a multi-analytical approach, combining non-destructive, micro-destructive, and destructive techniques to characterize the chemical composition and structure of the alloy, the production processes, as well as the state of preservation and, in some cases, the provenance of the raw materials. The main methods were X-ray fluorescence with Monte Carlo simulation (XRF-MCS) for the quantitative determination of elements and the structural characterization of alloys; scanning electron microscopy (SEM-EDS) and electron microprobe (EMPA) for the analysis of microstructures, chemistry and inclusions; micro-Raman spectroscopy and electrochemical techniques (VIMP, Mott-Schottky analysis) for the study of corrosion products and the state of conservation; X-ray microscopy (XRM) and neutron tomography (NT) were used for three-dimensional reconstruction of internal structures and understanding of manufacturing processes; finally, isotopic analysis of lead (LIA) and trace elements for the geological traceability of metals and the reconstruction of commercial and cultural contacts in the Mediterranean. In this thesis, seven case studies are reported, starting from the Nuragic finds, then the Etruscan ones, and finally the artifacts that testify to the contact between the two worlds. The results obtained showed that both civilizations were fully capable of selecting the type of alloy according to the final use of the artifact. The artifacts were mainly made of bronze with a low tin content (less than 11%), to which Pb was added, when necessary, to improve the working characteristics and lower the melting point. Both people were technically capable of producing structurally complex artifacts using the lost wax technique. Furthermore, the study of the production processes of some artifacts highlighted the choices by metallurgists in production, including repairs and modifications. The comparison among the Nuragic and Etruscan artifacts, the greatest differences emerge from the axes. The Sardinian axes, in fact, almost always feature bronze alloys with a low lead content (less than 5%), while the Etruscan axes analyzed show higher percentages (between 10 and 16%). The study of axes and ingots, as well as that of a rare statuette found in Lake Bolsena (VT), has provided new data and evidence on the exchange of raw materials in the Mediterranean, revealing a deep connection not only of a commercial nature, but also a social one, which fostered mutual technological and cultural contamination.