Sulfide mineral chemistry investigation of sediment-hosted stratiform copper deposits, Nahand-Ivand area, NW Iran

摘要

Copper mineralization in Nahand-Ivand area, NW Iran, appears as disseminated copper sulfides along a redox boundary between gray sandstone and microconglomerate and hematitic sandstones, siltstones and shaly marl. Geochemical analyses of the Nahand-Ivand deposits show as much 35 wt.% Cu and 730 ppm Ag in the gray sandstone. Electron probe micro-analysis (EPMA) was used to determine the mineralogical composition and distribution patterns of copper and silver-bearing phases mainly in pyrite and Cu-bearing sulfides. The EPMA data were essential for evaluating the distribution and partitioning of potential economically-valuable components between co-existing minerals. Furthermore, they contribute to a better understanding of the genesis of the Nahand-Ivand copper deposits and will guide further exploration in the region.