Evaluating the copy capacity of polyvinylsiloxane molds in quantitative surface texture analysis of ground stone tools

Polyvinylsiloxane (PVS) is a molding compound originally developed for dental applications that, over the past 50 years, has also been widely used in archaeology to produce negative surface replicas of artifacts, owing to its excellent detail reproduction and dimensional stability. However, most studies assessing its replication accuracy have focused on bones, teeth, and flint tools, leaving ground stone tools (GSTs) largely unexplored. This study fills this gap by assessing the accuracy of PVS molding on GSTs, whose uneven surfaces and heterogeneous textures present particular challenges for both qualitative and quantitative analyses. We tested the accuracy and precision of PVS copies on a reference collection of GST replicas based on archaeological artifacts from Upper Paleolithic sites, representing four diverse lithologies. Confocal profilometry was used to acquire microtopographic maps of selected areas, enabling in-depth statistical comparisons between original surfaces and corresponding molds, with emphasis on key roughness descriptors. The results show that PVS molds effectively capture fine surface details, making them suitable for rough and irregular surfaces, though minor deviations and parameters overestimation must be considered in quantitative traceological analyses. By evaluating replication accuracy, this study contributes to the refinement of analytical methodologies for GSTs and improves the reliability of functional investigations.