Mineralogical and petrographic analyses of a complex finishing plasters stratigraphy from a 17th century Sardinian Church

The work concerns the study of the original layers of mortar and finishing used in two historical phases of the Church of Madonna d'Itria in Orani (central Sardinia, Italy) which was built in the 17th century. The aim is to analyse the finishing pigmented layers that were superimposed between the 17th and 20th centuries. Furthermore, the study includes the analysis of the mortar substrate on which the pigmented layers were applied, to study their adhesion, mechanical resistance and composition. The general aim of the work is to highlight the techniques and raw materials used for made the finishing plasters and the presence of chemical-physical alteration processes aimed at restoration interventions.