Archaeological carved slabs of the Langobard art in churches of Peligna Valley and Spoleto (Italy): provenance of the stones

Abstract

In this study we investigate the provenance of the limestone and marble used to made carved slabs today placed in three churches located in Raiano and Vittorito (Peligna Valley, Abruzzo, Italy) and in Spoleto (Umbria, Italy). The slabs, representative examples of the Langobard art (Middle Ages), are dated approximately from 8th to 9th centuries A.D. and have the same pattern in terms of decoration, suggesting a progressive expansion of Langobards in central and southern Italy, after the foundation of the Pavia Kingdom.A multi-analytical approach, including petrographic characterization, chemical, carbon and oxygen isotope composition, was used for the complete characterization of these stones. The comparison of the results of the limestone slabs with those of the geological units outcropping in the area proves a local quarrying from the Calcari Cristallini Formation. Conversely, the carved marble slab has petrographic and isotopic signatures comparable to those of Carrara marble and presumable was imported from this famous locality.