At the crossroad of archaeology and experimental psychology, we addressed the issue of inter-individual variability in traditional ceramic shapes. The goal was to explore whether such variability could imply potter signatures. We setup a field experiment with five expert Nepalese potters, asking them to produce three shapes (replicated five times). The 2D profiles of the experimental productions were analyzed with a shape analysis method borrowed from biology. In a complementary experiment focusing on shape discrimination, the participants were asked to visually identify their own productions and those of their colleagues. Results indicated that the potters produced slightly but significantly different shapes. We assume that during apprenticeship individuals developed their own motor skills, which reflect upon the finished products. Interpreting shape variability in terms of individuals could provide supplementary information on the social organization of the production, either for modern or ancient periods. As for shape discrimination, our preliminary results indicated that a few potters visually distinguished individual signatures. Those craftsmen could play a key role in the selection and evolution of the traditional ceramic shapes.