Zoned Olivines of Bronze Age Metallurgical Slags of Southern Urals According to LA-ICP-MS Mapping

Abstract

Metallurgical artifacts including Cu-containing slag fragments were discovered at the Bronze Age settlements of Southern Urals. We have analyzed the slags of Sintashta culture from Kamenny Ambar settlement. The slags are mainly composed of olivine, magnetite and ultrabasic glass with rare inclusions of metallic copper; quartz, chrome spinels and serpentinite clasts are relic. The main rock-forming mineral of slags is olivine, in which the compositions of macro components and trace elements have been examined. The olivine is zoned: its central part is characterized by elevated forsterite minal with Co and Ni prevalence, while fayalite predominates on the peripheral parts and contains elevated concentrations of the remaining elements. The glass is characterized by higher Li, Ca, Al, Na, K, Sc, Ti, Ga, Nb, P, Pb, Rb, Sr, Ba, Zr, U and REE contents and indicates specific crystallization features as well as protolith composition and the fluxes used. Based on the LA-ICP-MS mapping, major and trace element zoning in olivine crystals has been considered in detail, and a crystallization scheme of metallurgical slags has been identified.