At Trans (Ille et Vilaine), a rescue excavation permitted the exploration of a medieval kiln and an associated dump, and the gathering of an important group of artifacts representative of the production which took place there. The search for the date of the functioning of this workshop and of the conditions of the desertion of the site has been the beginning of a collaboration between specialists in scientific techniques (thermoluminescence, archaeomagnetism, C 14) and archaeologists. The physical sizes obtained, together with the typological characteristics of the ceramics, permitted the advancement of knowledge of a local production of the tenth century. With a simple organization, easy to set up, cooperative studies of kilns discovered in France would advance our knowledge of pottery which possibly could serve as sure chronological elements in other excavation fields.