An archaeometric study of copper slags fom early Bonze Age I at Arslantape, Eastern Anatolia, Turkey

Abstract

ABSTRACT: 15 copper slags and 2 crucible fragments from the village of the Early Bronze Age I ( V1B2 period, 3100-2900 BC), at Arslantepe, Eastern Anatolia, Turkey, have been analyzed with energy dispersive X-ray fluorescence spectroscopy (EDXRF), powder X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) to determine the chemical and mineralogical composition and microstructures as well. The compositional analysis confirms the presence of iron, silicon, and aluminum as the significant elements in the copper slags with the modest level of copper and calcium, and low concentrations of sulphur, potassium, titanium, vanadium, chromium, manganese, zinc, molybdenum and strontium. Powder X-ray diffraction analysis reveals that quartz and fayalite are the major crystalline phases along with the magnetite as minor phase present in the analyzed slag samples. However, the mineralogical composition and SEM-EDS images indicates that some of the analyzed slags were the product of primary copper smelting and other might be formed during the works of metal. The presence of well-formed fayalite crystals in one analyzed slag sample indicates the specific thermodynamics condition, that is heating condition was well controlled during the smelting activities. Through EDXRF, the presence of low concentration of sulphur in all slag samples and the association of copper with sulphur in SEM-EDS image of one sample suggests that ancient metal workers might be exploiting some minerals as a copper ore that were associated with sulphur.