Analytical techniques applied to the study of mortars and coatings from the Tartessic archaeological site "El Turunuelo" (Spain)

Analysis of the mortars and coatings used in the walls of the archaeological site "El Turunuelo" has been carried out using spectrometric and thermo-physics techniques. Energy dispersive X-ray fluorescence (EDXRF), X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy coupled with X-ray spectroscopy (SEM-EDX) were used to shed light on the composition and morphology of the mortars used in the construction of the Tartessic building. In addition, studies of porosity and thermogravimetry, and comparisons with mortars from Roman and Arabic Iberian civilizations nearby have also been performed. From the results of EDXRF, Fe was found as the main element, while Ti, K and Ca were observed as minor components, and some traces of Si and Mn. The semiquantitative analysis performed by XRD and FTIR showed that the samples were mainly composed of aluminum silicates such as illite, dawsonite, muscovite, glauconite and calcium montmorillonite. SEM-EDX and stratigraphic studies showed the morphology of the samples, and the absence of Ca, which is in agreement with the visual assumption of adobe as the material used in mortars. This Ca fault was confirmed by the thermogravimetry results, where no weight losses were found in the heating curves.