Tracking the first bronze metallurgists of Western Europe: combined use-wear analysis and X-Ray Fluorescence synchrotron spectroscopy of a stone toolkit from Ploneour-Lanvern (Brittany)

At the turn of the second millennium BC in Europe, the development of copper and bronze metallurgies stimulated major economic shifts, with the emergence of elites and far-reaching diffusion networks. However, the exact organization, techniques, processes, and equipment employed in this early copper and bronze metallurgy still remain poorly understood. In this context, our aim has been to identify the first stone toolkits used by Early Bronze Age metallurgists on a site in western Brittany (France), a region connected to the so-called Atlantic complex. The combination of use-wear analysis and Synchrotron X-ray fluorescence spectroscopy (XRF) imaging highlights a correlation between the distribution of diagnostic use-wear traces (smoothing and micropolishes) related to metal ore processing or metal objet shaping and elemental residues of copper and zinc. These results demonstrate the existence of copper ore processing in western Brittany during the Early Bronze Age (2200–1900 BC). They also highlight the diversity of the stone tools involved in metal production. Finally, this comprehensive methodology underlines the potential of functional analysis of macrolithic tools to reveal the existence of metal production. This is particularly relevant for archeological sites where the structures of metallurgical production are barely visible and often unrecognizable and where metallic objects are rare due to their intensive recycling and diffusion.