Pottery samples from one Cerny Culture site and three Chasséen sites in the Oise valley are examined. From the Cerny onwards one notes a new mastery of firing temperatures, producing sherds in an early stage of vitrification and vessels of greater solidity. The use of local materials widely available near the sites, both for clay and temper, is not in contradiction as far as the latter is concerned with the cultural development of technical practices observed on a broader regional scale.