Ore Minerals and Metal Distribution in Tailings of Sediment-Hosted Stratiform Copper Deposits from Poland and Kazakhstan

Abstract

This study, carried out in tailings from two sediment-hosted stratiform copper deposits in the Lublin-Głogów Copper District in Poland (Kupferschiefer-type deposit) and Zhezkazgan (cupriferous sandstone-type deposit) in Kazakhstan, analysed the mineralogy of copper, zinc, and lead minerals as related to metal accumulation in sediments. Microscopic study in reflected light and SEM–EDS (Scanning Electron Microscope—Energy Dispersive Spectrometer) analysis, as well as chemical diversity in the used INAA (Instrumental Neutron Activation Analysis), ICP (Inductively Coupled Plasma), and AAS (Atomic Absorption Spectroscopy) methods in 35 samples from Kazakhstan and 35 from Poland were examined due to their diversity. In both tailing deposits in Kazakhstan and Poland, heavy fractions were dominated by copper sulphides: chalcopyrite (CuFeS2), bornite (Cu5FeS4). and chalcocite (Cu2S). Moreover, sphalerite, galena, and cerussite have been recognized as a carriers of Zn and Pb. Their geochemistry was dominated by Cu, showing a mean content of 2500 ppm, in both Poland and Kazakhstan. Zinc and lead also occurred, showing a content of approximately 200 ppm and 500 ppm in Poland, and 1500 ppm Zn and 2500 ppm Pb in Kazakhstan, respectively. Grain size analysis indicated that the dominant grain size in both districts corresponded to the silt and fine sands fractions. Copper, zinc and lead sulphides accumulated in fine fractions in tailings from Kazakhstan (in sandstones and quartz grains), and mainly in coarse fractions in Poland (within carbonates, sandstones, and black shales). Mineralogical and geochemical features should be taken into consideration when assessing potential metal sources of technogenic materials.