War and commercial exchanges in the late medieval Aegean: Investigating the metal provenance of the Chalcis Hoard

•First metal provenance study of medieval armor from Chalcis (Euboea Island, Greece), based on the analysis of lithophile trace elements in slag inclusions.•Results highlighted several metal supplies.•Comparison with reference sets of European armor strengthen the hypothesis of a northern Italian manufacture for some pieces.•Some chemical tracers such as Ti but also Th, U and Hf might suggest the use of titanium-rich iron ores (black sands) and point to regional metal resources (Macedonia). At the end of the Middle Ages the Aegean was an active trade area, connected to numerous exchange networks. Arms and armor were strategic products, exchanged over extra-regional distance through the Mediterranean trade. To shed light both on military goods manufacturing and Aegean trade networks, this paper focuses on the archaeometric examination of thirteen medieval pieces of armor found in Chalcis (Euboea Island, Greece), then a Venetian hub. Our aim was to perform a provenance study of the metal, based on the LA-ICP-MS analysis of trace rare earth elements in the slag inclusions of the metal artefacts, combined with statistical approaches to compare the chemical signatures with published reference groups. Until now most of these objects were considered imported from northern Italy, whereas the chemical approach highlighted several subsets. Seven samples have a chemical signature compatible with a reference group of Italian style defenses, while others present different chemical tracers such as high Titanium content, that could indicate the use of regional metal resources (Macedonia). These results bring new insight into the Aegean trade network opening the door to more extensive studies in the area.