Material journeys: unravelling itineraries of granite shafts in medieval Pisa

This study examines the trajectories of granite column shafts in medieval Pisa as a proxy for shedding light on its architectural and economic history. Using magnetic susceptibility measurements on a sample of 201 shafts, we were able to identify the origins of granite from quarries in Elba, Corsica, Sardinia, Anatolia, and Egypt. By associating the origins of the columns with the chronology of the buildings and the morphology of the individual shafts, it is possible to trace some characteristics of the dynamics of material procurement and trade in the early and late Middle Ages. Findings reveal organized material procurement, with reused shafts particularly prevalent in 11th-century churches, which highlights the role of columns in the formal and symbolic language of city. The research demonstrates how the integration of archaeometric analyses and the study of urban topography could foster a more comprehensive understanding of material reuse and resource management in medieval urban centres.