Stamped tiles from Bomarzo-Piammiano (Viterbo, Italy): local production or import?

Archaeological research carried out at Bomarzo-Piammiano (Viterbo, Italy) brought to light a large rural settlement dating from the seventh century B.C. to the sixth century A.D.. Located atop a plateau overlooking the Tiber valley, the site of Piammiano and the adjacent fields produced evidence of 51 stamped bricks mainly made by the figlinae Caninianae, Domitianae, gens Domitia, Terentianae, Publilianae, Tonneianae, Tur( ) and late-imperial workshops; some products de Licini(anis) have also been found. The archaeological evidence from the territory of Bomarzo, together with the availability of natural resources, suggests the local production of these bricks. The principal objective of the present research is to provide chemical and mineralogical data which will permit the testing of this hypothesis. Both the chemical homogeneity of the bricks found at Piammiano and the similarity of both major and minor elements in these bricks and in the local natural clays suggest a local clay source for the majority of the bricks examined. Moreover, evidence of two brick production sites recently found in the territory of Bomarzo and Attigliano lend further support to the hypothesis of a local production.