A provenance study on indigenous and Phoenician bronzes: Insights on the Early Iron Age copper sources of the southwestern Iberian Peninsula

Abstract The diachronic evolution of the Early Iron Age copper-based metallurgy in southern Portugal is behind the research now carried out with the aim of determining the copper provenance in bronzes from two partially coeval settlements. Castro dos Ratinhos shows a metallurgy of Late Bronze Age indigenous tradition, while Quinta do Almaraz with a strong Phoenician influence, presents a more evolved technology, apparently affiliated with regions bordering the Eastern Mediterranean. Our integrated approach crossed Pb isotopes, trace elements, archaeological and historical data. Studied artefacts comprised eight bronzes ( c. 10 wt% Sn) from Castro dos Ratinhos and ten artefacts from Quinta do Almaraz, namely three coppers and seven bronzes ( c. 6 wt% Sn). Trace elemental profiles, performed by inductively coupled plasma mass spectrometry, suggest a diversity of copper sources and differentiate these collections effectively, primarily due to higher zinc and gold contents at Quinta do Almaraz. The Pb isotope signatures, determined by multi-collector inductively coupled plasma mass spectrometry, indicate the use of distinct ore deposits by those communities. Castro dos Ratinhos shows a significant exploitation of Iberian Pyrite Belt mines, most of them located not very far from the settlement. In contrast, the evidence of Quinta do Almaraz demonstrates the existence of significant trade routes from regions outside the Iberian Peninsula, specifically Sardinia and, likely, the more distant region of Anatolia. The existence of such metal trade routes connecting the Central and Eastern Mediterranean with the Iberian Peninsula during the Early Iron Age is becoming increasingly evident as metal provenance studies are carried out.