Materiali, colori e trasparenze nell’architettura senese a facciavista (XII - primi XVI secolo)

The mineralogical-petrographic studies carried out over the last few decades concerning the facades of the historic centre of Siena have led to an outstanding growth of knowledge on the colors and the exposed finishing techniques adopted between the end of the 12th and early 16th centuries. A complex and fascinating picture emerges that goes beyond the simple dichotomy between plaster and rough masonry. In general, the natural color of the building materials was not hidden but corrected in its irregularities and enhanced by pigmented or transparent treatments which accentuated and directed its tone. The results achieved allow some overall assessments, with significant repercussions on both the historical and the conservation perspectives.