Analytical Assessment of Chaltasian Slag

Chaltasian, Iron Age II, in the Central Plateau of Iran, excavated by Islamic Azad University, Varamin-Pishva Branch. Metallurgical studies were carried out to identify oxides, Ca-rich silicates and metallic phases in the slag material, using wavelength dispersive X-Ray fluorescence (WDXRF), followed by an analysis of one sample under the polarizing microscope: plane polarized light (PPL) and cross polarized light (XPL). Based on the analyses, it has been concluded that these six copper slag remains have a considerable amount of silica, which had been added to the smelt to increase its fluidity. Analyses showed a clinopyroxene microstructure in a glassy matrix for five samples, and a barite source, from a probable lead-zinc source in limestone, for the other sample. The absence of arsenic in these copper slags could show a paradigm shift in copper production in this space-time grid. According to the low amount of slag present on site, on the one hand, and the application of relatively advanced extraction technology on the other, this research introduces Chaltasian as an Iron Age II small copper production centre in the Central Plateau of Iran with a locally-developed copper extraction technology.