Conservation And Restoration Of Historic Stone And Plaster Of Kutubiyya Mosque (Morocco)

Abstract

The problem of preserving our built heritage is a cultural and scientific challenge of great and even strategic importance, given that many monuments in Morocco have suffered significant deterioration. Since the renovation of facade and interior plasters is among the most common tasks in restoration projects, it is important to study the composition of these stone and plasters to ensure the compatibility of the materials used and their proper interaction with the substrate.To this end, our work involves characterizing the stone and plaster from the enclosure of the Kutubiyya, as well as the materials used for the restoration of the wall, using mineralogical, chemical, and petrographic characterization methods such as X-ray diffraction, X-ray fluorescence, and petrographic analysis.The masonry stone is a marly limestone with characteristics typical of hard rocks, and the primary exterior plaster is made of lime and silty sand, with the addition of a percentage of gypsum to accelerate setting. X-ray diffraction analysis revealed the presence of the following crystalline phases in the original masonry stone of the historical Kutubiyya Mosque: calcite, clays, quartz, and dolomite. Meanwhile, X-ray fluorescence allowed the determination of the major elements in our plaster (namely SiO2, SO3, CaO, Al2O3, MgO, and Fe2O3). These results highlighted differences in the chemical composition of the original and restoration palsters, thereby influencing the quality and efficiency of the restoration of the Kutubiyya in Marrakech.