Mineralogical and Geochemical Characteristics of Lead-zinc Ore Deposits, and Potential Accompanying Components in the Cho Don - Cho Dien Area, Bac Kan Province, Vietnam

The Pb-Zn mineralization in the Cho Don - Cho Dien ore districts often occurs in 2 types: (1) oxidized ore near to the surface and (2) sulfide ore at deeper section. Based on microscopic observations, sulfide ores can be divided into sphalerite-galena-pyrite and/or galena-sphalerite mineralization types. To examine the geochemical features of the Pb-Zn ores, SEM-EDX and ICP-MS analytical methods were performed in this study. Previous δ34S data of Pb-Zn concentrates, and sulfide minerals from various deposits suggest that the Pb-Zn ore-forming fluids might be related to the felsic-granitic magmatic activities rather than a genesis of stratiform type. Geochemical data show that the major, minor, and trace element compositions of lead-zinc ores have wide ranges of variation even in each deposit. The sulfide ores are generally higher in economic components than those in the oxidized ores. The positive correlations between Pb-Ag can be found in the entire dataset, whereas excellent Zn-Cd correlation can only be observed from Cho Don ore samples. Apart from the principal components (Pb and Zn), the ores also contain other accompanying elements that supply high-technological manufacturing industries. Of which As, Cu, Ag, Sb, and Cd could be potential by-products and can be extracted during smelting Pb/Zn concentrate processes, and need more detailed studies for every deposit.