Development and evaluation of new treatments for the conservation of outdoor stone monuments

JRA1 is one of the two Joint Research Activities in the framework of the European Project Eu-Artech (Access Research and Technology for the Conservation of the European Cultural Heritage). The project consists of a consortium among twelve internationally distinguished European institutions operating in the field of conservation of Cultural Heritage. Within Eu-Artech activities, JRA1 studies new treatments for the conservation and restoration of stone and bronze monuments, in order to deepen the knowledge on inorganic materials used as conservative products, comparing them to the traditional compounds. This paper presents some results achieved within the research activity carried out on stones. Two inorganic products have been tested: barium hydroxide and ammonium oxalate, both performing as a consolidant and as a protective, and compared with products widely used in Europe. Different lithotypes have been selected for the experimentation: limestones (Lecce and Anca Stones), sandstones (Firenzuola and Santafiora sandstones) and marble (Gioia Marble). The work aimed at deeply defining the properties of the inorganic treatments, in order to outline "good conservation practices" and improve knowledge on materials and methods in conservation.