First Finding of E arly Medieval Iron Slags in S ardinia ( I taly): A Geochemical–Mineralogical Approach to Insights into Ore Provenance and Work Activity

At S anta F ilitica, a R oman settlement in north‐western S ardinia occupied until the ninth century ad , archaeological excavations have found the remnants of a furnace consisting of a semi‐circular base made of stony slabs and tiles bound with clay. The furnace is attached to a wall of R oman age. Layers of the sixth century ad , bearing several variously oxidized slags, were found close to the furnace. These findings first testify to an ironworks in S ardinia, within a well‐defined context. XRPD and SEM – EDS mineralogical and textural analyses suggest that the slags derive from a bloomery and smithing work that was the first evidence of this type documented in S ardinia during the E arly M iddle A ges. C hemical analyses (performed with IC P and INAA ) of rare earth elements and trace elements in two slags and in two S ardinian iron deposits allow some conclusions to be drawn on the local provenance of the ore. Our comparison of the S ardinian findings and some slags representative of archaeological smelting sites at the front of E lba island—the largest and longest lived iron‐working sites in the Mediterranean—also improves the methodology with which iron slags derived from different ores are compared.