Degradation of stone materials in the archaeological context of the Greek-Roman Theatre in Taormina (Sicily, Italy)

In the present work results on the degradationphenomena of stone materials in the Ancient Theatre ofTaormina, one of the most important Greek–Roman monumentsof Sicily, are reported. Artificial stone materials in differentconservation conditions were investigated. Samplesof salt efflorescences from brick walls and degraded settingmortars were taken from the open gallery in “summa cavea”.The chemical, physical and structural characterization wasperformed by means of X-Ray Photoelectron Spectroscopy(XPS), X-Ray Diffraction (XRD) and X-Ray Fluorescence(XRF), both in situ and ex situ.Results showed that the deterioration of stone materialsis due to the aggressive action of the environmentagents. Soluble salts, such as chlorides, sulphates and nitrates,were found in efflorescence samples. Mortars wereaffected by a decomposition process induced by sulphates’attack.