Figure 1From: XPS characterization of (copper-based) coloured stains formed on limestone surfaces of outdoor Roman monumentsEnlarged views of the two studied monuments in Rome. (a) and (b) ‘Statua dello Studente’ (by A.Cataldi, 1920- University city, La Sapienza); (c) and (d) ‘Vittoriano’ (by G.Sacconi, 1885-1911- Piazza Venezia).Back to article page