Determination of enriched elements in the Sarcheshmeh Cu mine tailings, Rafsanjan, Kerman province

Tailings are the most important mine waste which are produced in enormous mass during the mineral processing of the sulfide ores, especially Cu-porphyry type. The main object of this study is to determine the enriched elements in the tailings of the Sarcheshmeh mine; as one of the biggest Cu-porphyry mines in the world. For this purpose, 90 surface and subsurface samples (to about 10 m depth) were collected from fresh and un-oxidized tailings in the available parts of the tailings dam. Fourteen composite samples were prepared for multi-elemental geochemical analysis using inductively coupled plasma mass spectrometry (ICP-MS) method and preparation of polished sections. Microscopic studies showed that pyrite is the main sulfide mineral in tailings, but chalcopyrite and chalcocite also were found in some samples. According to the normalized enrichment factor, among the more than 60 investigated element (1) Sb (3.9 ± 1.1 mg/kg), W (21.4±8.8 mg/kg), As (21.4 ± 2.3 mg/kg), Bi (33 ± 10 mg/kg), Au (33 ± 10 µg/kg) and Ag (1.02 ± 0.15 mg/kg) have significant enrichment; (2) Cu (1350 ± 478 mg/kg), Fe (4 ± 0.52 %) have high enrichment and (3) S (2.75 ± 0.6 %), Re (21 ± 0.07 mg/kg), Te (0.38 ± 0.23 mg/kg), Se (4.81 ± 0.95 mg/kg) and Mo (91 ± 18.7 mg/kg) have extremely high enrichment compare with the crustal abundance and normal values in un-mineralized granodiorite rock (mean ± standard deviation). These elements are chalcophile or have high potential for presence in sulfide minerals such as pyrite and chalcopyrite. The obtained results well consistent with the geochemical signatures of elements in the Cu-porphyry deposits and determine the elements that have economical/environmental importance in the Sarcheshmeh mine tailings.