In order to study the processes of salt weathering of monumental stones, several samples were partially immersed inudsodium, potassium and magnesium sulphate solutions which ascended through their capillary network and, eventually,udcrystallized. This procedure pretends to simulate the conditions in which foundations and lower walls of buildingudstructures are, within the zone of capillary rise of saline groundwater. Mass transport and the rhythmic nature ofudcrystallization fronts inside samples reminds the Liesegang phenomenon, so they have been considered as a form ofuddissipative structures. The saline deposits developed on the surface of the samples were efflorescences (mirabilite andudepsomite), subefflorescences (picromerite, aphthitalite and arcanite) and crusts (aphthitalite and arcanite). The mostuddevastating effects resulted from massive crystallization inside the samples or from surface peeling due to the developmentudof subefflorescences or crusts.
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