Mineralogical and geochemical characterization of Roman slag from the archaeological site near Mošnje (Slovenia)

Abstract

Roman slag from the archaeological site near Mošnje (NW Slovenia) was studied with respect to its mineralogical and geochemical characteristics. Samples were analysed with light microscopy, X-ray powder diffraction (XRD), scanning electron microscopy with an energy dispersive spectrometer (SEM-EDS) and Raman microspectroscopy. A chemical investigation was carried out using inductively coupled plasma-atomic emission spectroscopy (ICP-ES) to determine the major elements. The investigated slags are recognized as iron slags, grouped into two main classes according to their chemical and mineralogical compositions. The first group is characterized by high Fe2O3 and low SiO2 contents and the second by high CaO and SiO 2 and low Fe 2 O 3 contents. The phase occurrence obviously depends on the chemical composition as the first group mainly consists of fayalite, wüstite and magnetite, and the second one of augite, leucite, hedenbergite, monticellite and kirschsteinite.