"PISTA : Patina and iron on stone tools from Africa"

Taphonomic processes alter the archaeological record and complicate interpretations of artifacts such as stone tools. Distinguishing post-depositional modification from modification related to cultural use can therefore be challenging. Drawing on stone tools made of hornfels presenting double patinas and coloured coating/deposits from the Middle Stone Age and Late Stone Age layers of Bushman Rock shelter (Limpopo, South Africa) PISTA aims to investigate the modifications of hornfels induced by natural phenomena and anthropic use. The goal is to build an experimental reference collection of patina and iron coating/deposit on surfaces of hornfels for comparison with African Late Stone Age and Middle Stone Age stone tools.