A number of techniques were employed to detect morphological and chemical changes on the irradiated surfaces. Stereomicroscopy was used to describe morphological and colour changes. Scanning electron microscopy (SEM) at low vacuum served to analyse the effects on the surface of the lichens, while SEM-BSE of the polished transversal cross sections was applied to assess effects inside the crust and in the lithic substrate. FT-Raman spectroscopy was employed to detect possible structural and chemical changes.