Authors:V. Rodríguez-Lugo, L. Ortiz-Velázquez, J. Miranda, M. Ortiz-Rojas and V. Castaño
The characterization of samples of painted plasters obtained from the archaeological site of Xochicalco, in Central Mexico,
is presented. Elemental concentrations of the painted layers were obtained by using proton induced X-ray emission (PIXE).
The main crystalline structures of the samples are identified with the help of X-ray diffraction (XRD), while the microstructure
is studied by scanning electron microscopy (SEM). The information resulting from the application of these three techniques
is used to achieve more accurate values for the elemental concentrations. Additional data regarding organic components of
the paintings was obtained through Fourier transform infrared spectrometry (FTIR). Although the latter results only provided
reliable data on inorganic components, they help to clarify the results from XRD and confirm those of SEM.
Authors:E. Carreto, C. Piña, H. Arriola, A. Barahona, N. Nava and V. Castaño
Iron-doped silicate (zircon), prepared by a ceramic method with the addition of LiF as mineralizer, was analyzed by X-ray powder diffraction (XRD) and 57Fe Mössbauer spectroscopy to obtain information on the solid solution formation. The results of X-ray diffraction and Mössbauer spectroscopy have shown that only a small fraction of iron, about 1.5 mol%, is incorporated in the zircon structure as paramagnetic Fe3+ species while the remaining Fe3+ cations form magnetic -Fe2O3 particles which are trapped within the zircon matrix.