Demo conferences: based on interaction, the experience combines manipulations made with the public and explanations of researchers Cut stones are the witness of the development of our intelligence during hominisation, but also of the "cultural markers" of human communities. They will become the products of real craftsmen during the Neolithic. We invite you to discover and manipulate these objects, and to familiarize yourself with the different techniques of size invented by our ancestors throughout Prehistory that raise many comments and big questions. By Jacques Pelegrin, Prehistorian at the CNRS