The Degradation of Stone. Studies and Reports in the 1950s on the Conservation of Stone Material in Florence.

Abstract

The paper examines the issue of the deterioration of stone materials in architecture. The problem is framed by highlighting the main trends observed throughout history, then delving deeper into the intense debate that took place in Florence during the mid-1950s. In the past, conservation interventions for stone materials were carried out with the aim of protecting the surfaces of the materials, but in the 19th century, the importance of internal consolidation of the stone began to be understood, thanks in large part to significant progress in the industrial field. The earliest techniques used silicates. Renowned restoration projects, such as that of Notre Dame in Paris, showcased the use of the first consolidation treatments, marking them in history as precursors of stone hardening. From the early 20th century onwards, institutions such as the Royal Museum of Berlin and the Central Institute for Restoration in Rome played a key role in the development of conservation techniques, laying the foundations for contemporary conservation science. This paper specifically aims to examine the debate on monument conservation in 1950s Florence. At the center of the discussion were the respective directors of the Opificio delle Pietre Dure in Florence and the Istituto Centrale per il Restauro. Through archival research and a careful reading of published sources, it has been possible to reconstruct the trends and positions of the two institutions regarding the conservation techniques of stone surfaces, as well as to bring to light the products used in the restoration of the most important Florentine monuments.