Palazzo Cristofanello a Cortona: un esempio di evoluzione storica, scientifica e culturale sul restauro lapideo.

Cristofanello Palace, situated in Cortona (Arezzo) and projected by the architect Cristofanello, is one of the most important buildings of the tuscan town. The building, subjected to different restoration phases, is an example of the different approaches to the restoration of a public building. The present paper highlights the problems arising from the treatment of some sandstones with specific mineralogical, petrographycal and physical characteristics and underlines the need of a monitoring of the intervention, in order to avoid any emergency’s situation. The paper shows also the praxis that must be carried out in the case of a scientific and technical support to a restoration project.