New virtual approach to the study of metallurgy through the analysis of slice marks from the Chalcolithic site of Zanjillas (Torrejón de Velasco, Madrid, Spain)

Although the discovery of metal objects is not common in Chalcolithic or Bronze Age sites, the study of bone surface microscopic grooves from animal butchering can yield evidence of the use of metal artefacts in these contexts. Additionally, the presence of slice marks made with metal objects in Chalcolithic and Bronze Age sites has highlighted the use of metal in common practices beyond their ornamental application, as usually expected at the early stages of metallurgy. Here, we present the study of the slice marks found at the Chalcolithic site of Zanjillas, using geometric morphometrics and machine learning algorithms, with the aim of identifying the nature of the tools used for carcass processing at the site. For this purpose, we replicate previous analyses considering slice marks produced with lint flakes and metal tools to generate a referential framework that serves as comparative to the Zanjillas sample. Our results suggest that most of the domestic activities related to carcass skinning, defleshing, or evisceration in Zanjillas were still performed with flint artefacts.