Il reimpiego dei materiali lapidei come pratica di cantiere in età medievale

The contribution is dedicated to the archaeology of building production and to the value of recycling in the building economy. The focus is on the practical aspects of recycling, starting with the materials reused: type, quantity, percent age, size, association with other materials, including its organization. In particular, the paper deals with the choice of materials at the procurement stage, their intended use and any adaptation or reworking, and the methods of installation. Sometimes these different materials became rubble, probabily residues from firing in lime kilns, given the evident ex posure to a heat source or deliberately crushed and broken. In some case the different stone finds continued to circulate and be recycled in the various constructions that followed in the same areas from the medieval phase onwards. The case of the Comacchio bishop’s palace, an example of heterogenous selective reuse, and the case of the Piazza dei Miracoli in Pisa, an example of homogeneous selective reuse, are examined