Occurrence of Manganese in the Zhaxikang Lead-Zinc Deposit from Tibet Investigated by Energy Scanning Electron Microscope and X-ray Diffraction Methods

The Zhaxikang Pb-Zn polymetallic ore deposit, the first SEDEX-modified by hot spring type Mn-Fe-Sb-Pb-Zn-Ag deposit discovered in China, is associated with Pb, Zn, Ag, Sb, Cu, S, Mn, As and other elements. The concentration, mineral species, dissemination and inclusion of Mn in the Zhaxikang Pb-Zn deposit were studied by chemical analysis and examination using Petrographic Microscope, Scanning Electron Microscope and X-ray Diffractometry. The analysis showed that the content of ore-forming elements Pb and Zn were 6% and 4%, and the content of the associated component Mn was 4.36%. The main mineral compositions of the Zhaxikang Pb-Zn polymetallic ore deposit are galena, sphalerite, pyrite, arsenopyrite and rhodochrosite. The useful composition of manganese minerals in the mine mostly occurs as rhodochrosite and iron rhodochrosite, which closely associated with sphalerite and galena, an important carrier of mineralization stage, inlay on the edge, intergranular and gap between quartz, pyrite, sphalerite and arsenopyrite. The others occur in siderite and smithsonite with isomorphism forms. The content and occurrence of Mn in Zhaxikang Pb-Zn ore metallurgical produts were analysised, which shows that the comprehensive utilization of Mn is of high value. The mass fraction of Mn in the lead ore, lead concentrate, zinc concentrate and tailings was 4.36%, 0.51%, 0.95% and 5.36%, respectively, indicating that little Mn enters into lead concentrate and zinc concentrate, but mostly in tailings. Mn is mainly in rhodochrosite form in lead-zinc tailings, which can be comprehensively recovered and utilized by a high intensity magnetic separation process.