Between the hammerstone and the anvil: bipolar knapping and other percussive activities in the late Mousterian and the Uluzzian of Grotta di Castelcivita (Italy)

Hammerstones and anvils are among the oldest tools used by hominins to performa variety of tasks including knapping activities. The bipolar technique on anvil is well documented in Prehistory since the Lower Palaeolithic and is usually considered to be an expedient technique in comparison to other knapping systems. This technique plays a pivotal role in the Uluzzian technocomplex lithic production where it is largely used. In the present study, we analyse the anvils and hammerstones recovered in the Mousterian and Uluzzian layers of the site of Castelcivita (Campania region-southern Italy) by a multi-disciplinary approach. Our aim is to investigate the function and functioning of anvils and hammerstones by evaluating the presence and the role of bipolar knapping in these two assemblages. To do this, we integrated techno-functional analysis (sensu Boëda) and use-wear study, by defining each techno-functional unit (transformative and prehensile unities) of anvils and hammerstones and identifying the specific use-wear left by the bipolar technique by means of a dedicated experimental programme. The obtained results allowed us to observe different technical behaviours, concerning both the production and the use of hammerstones and anvils, between Mousterian and Uluzzian. Differences were encountered in the selection of raw material (limestone in the Uluzzian, sandstone in the Mousterian) and in the technical way of approaching the tool as well as in the function: the Mousterian anvil was used 'as is' for crushing materials, unlike the Uluzzian anvils which were exclusively employed for bipolar knapping, adapting after their original volume. Hammerstones were mainly used as pestles or retouchers in the Mousterian and for direct percussion in knapping activities during the Uluzzian.