The characterization of archaeological ceramics according to their chemical composition provides essential information about the production and distribution of specific pottery wares. If a correlation between compositional patterns and local production centers is assumed, pottery manufacturing and trade and, more generally, economic, political, as well as cultural relations between communities and regions can be investigated. In the present paper, the combined application of portable XRF and statistical analysis to the investigation of a large repertory of ceramic fragments allowed us to group the assemblage by identifying geochemical clusters. The results from the chemical and statistical analysis were then compared with reference ceramic samples from the same area, as well as with macroscopic and petrographic observations to confirm, coalesce or sub-divide putative sub-divisions. The study of 141 samples from different sites located within a wide area spanning across the Colline Metallifere and the coast (Monterotondo Marittimo, Roccastrada, Donoratico, and Vetricella) provided new clues for a new interpretive archaeological framework that suggests that there was a well-defined organization of pottery manufacturing and circulation across southern Tuscany during the early medieval period.