The production of ceramic materials in Roman Pavia: An archaeometric NAA investigation of clay sources and archaeological artifacts

Part of a research program on cultural heritage aimed to elucidate the prod uction of ceramic artifacts in Roman Pavia is devoted to the localization o f the possible sources of raw materials (claypits) as well as to the techno logical production processes. Clay samples were collected in two different areas nearby Pavia, Lomellina and Oltrepo. Some of these samples were also fired at 950 degrees C. Archaeological ceramic samples, mostly bricks and t ires of Roman age, were obtained from excavations of Roman settlings close to Pavia. All samples were submitted to instrumental neutron activation ana lysis for the determination of Ca, Fe and a number of trace elements. Resul ts indicate (1) fired and raw clay samples keep the same elemental fingerpr int so that only raw samples data can be used in archaeometric studies; (2) some parameters based on rare earth elements are useful to discriminate th e clay samples from the two investigated areas; (3) clay discrimination is confirmed also by discriminant analysis; and (4) the insertion of the eleme ntal composition data of the ceramic artifacts in the statistical treatment allows one to assign the artifacts to one of the investigated areas and co nfirms that, at Roman times, the production of ceramic building materials w as mostly based on the use of local prime matter.