Swelling clays in stone materials of the built heritage of Córdoba (Spain)

A significant discovery in the study of Medina Azahara's built heritage reveals that swelling clays, particularly smectite and chlorite-smectite mixed layers, are prevalent in the stone materials used. These clays, found in concentrations of 5-30 wt%, contribute to the weathering of the stone, exacerbating decay processes due to environmental changes like humidity fluctuations. The research analyzed samples from the Palacio de los Páez de Castillejo and three types of stone from Madinat Al-Zahra, highlighting the detrimental impact of these clays on the overall porosity and stability of the stone. This finding underscores the importance of understanding the mineralogical composition in preserving historical structures.

(Ed.). (2014). Swelling clays in stone materials of the built heritage of Córdoba (Spain). Science, Technology and Cultural Heritage, 279–286. https://doi.org/10.1201/b17802-42