Mineralogical and Microstructural Analysis of Mortars from Kushite Archaeological Sites

This paper presents the XRD, XRF and porosimetry analyses and SEM-EDX observations of nine mortars: three Egyptian plasters (New Kingdom, fifteenth to eleventh century B.C.) and six Meroitic mortars (first century AD) collected on temples, palaces and pyramids in archaeological sites located between the Third and Fourth Cataract. The two first Egyptian samples were mainly composed of gypsum plaster. The third one and a bedding mortar collected on a Meroitic pyramid were composed of siliceous sand bound by about 30% kaolinite-rich clay. A coating mortar collected on another Meroitic pyramid, probably highly lixiviated, had a similar composition with only 11% clay. The other Meroitic samples appeared as conventional fully carbonated lime-sand mortars. The compositions of the decorative surface layers varied from clay to lime or lime-and-gypsum, in the form of painting or applied as fresco. This extreme diversity of compositions observed is particularly interesting from an archaeological point of view. The knowledge of the various techniques used enables us to have a better understanding of foreign influences on building workers in ancient North Sudan.