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The Nanmushu Zn–Pb deposit is a large-scale and representative deposit in the Mayuan ore field on the northern margin of the Yangtze Block. This study investigates the trace element geochemistry of sphalerite from this deposit using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The results show that the main trace elements in sphalerite include various trace elements, such as Mn, Fe, Cu, Ga, Ge, Ag, Cd, Pb, Co, Hg, Tl, In, Sn, and Sb. Among them, Ag, Ge, Cd, and Cu are valuable components that may be recovered during mineral processing or smelting techniques. The histograms, LA-ICP-MS time-resolved depth profiles, and linear scan profiles indicated that most trace elements occur in sphalerite as isomorphs, while partial Pb, Fe, and Ag occur as tiny mineral inclusions. The correlation diagrams of trace elements revealed that Fe2+, Mn2+, Pb2+, and Tl3+ can substitute Zn2+ in sphalerite through isomorphism. In sphalerite, Cd2+ and Hg2+ together or Mn2+, Pb2+, and Tl3+ together can replace Zn2+, i.e., ((3Mn, 3Pb, 2Tl)6+, 3(Cd, Hg)2+) ↔ 3Zn2+. Moreover, there is a mechanism of Ge4+ with Cu+ or Ga3+ with Cu+ replacing Zn2+ in the Nanmushu deposit, i.e., Ge4+ + 2Cu+ ↔ 3Zn2+ or 2Ga3+ + 2Cu+ ↔ 4Zn2+. Furthermore, the trace element compositions indicate that the Nanmushu Zn mineralization occurred under low-temperature conditions (<200 °C) and should be classified as a Mississippi Valley-type (MVT) deposit. This study provides new insights into the occurrence and substitution mechanisms of trace elements in sphalerite and the metallogenic constraints of the Nanmushu deposit. [ABSTRACT FROM AUTHOR]

The Baisong deposit in Kaili is a representative Pb-Zn deposit in eastern Guizhou province, but its research is relatively weak. In this paper, the mineralogical study of this deposit was carried out in detail using an ore microscope and TIMA. The results show that the ore minerals of the Baisong Pb-Zn deposit are mainly sphalerite, galena, and smithsonite, while the gangue minerals are mainly dolomite and a little bitumen. The ores are characterized by brecciform, vein-like, disseminated, massive, variegated, honeycomb, and stellate structures, and mainly consists of hypidiomorphic to automorphic, allotriomorphic, and metasomatic texture. The wall rock alterations near the ore body are mainly dolomitization, followed by bituminization, a small amount of pyritization, and calcilization. The ore deposit is dominated by sulfide ore, but some oxidation has occurred near the surface of the ore bearing layers. The characteristics of the ore and mineral indicate that the deposit has experienced three epochs: l) Pre-enrichment of ore-forming materials occurred in the sedimentary-diagenetic epoch; 2) Extensive hydrothermal activity occurred in the ore-forming epoch and a large amount of lead-zinc sulfide and dolomite precipitated, and 3) Ore oxidation occurred in the near-surface environment in the supergene epoch. The mineralization temperature of this deposit is low, and the organic matter of oil and gas may be involved in the mineralization, and it belongs to the MVT deposit. This research is in helping to guide the later exploration of lead-zinc minerals and comprehensive utilization of mineral resources in this deposit. [ABSTRACT FROM AUTHOR]