Chemical Fingerprinting Characteristics of Pyrite from the Lianhuashan Gold Deposit, Chifeng, Inner Mongolia, and Their Significance in Ore Deposit Geology

The Lianhuashan gold deposit is situated on the northwestern margin of the Chifeng-Chaoyang Gold Metallogenic Belt. Due to prolonged mining activities, the current retained gold reserves are insufficient to sustain continuous production, necessitating enhanced exploration efforts in the deep and peripheral zones. This study investigates the metallogenic mechanisms and deposit types through the analysis of pyrite compositional typomorphism and proposes guiding recommendations for prospecting. The results indicate that: The Co/Ni elemental ratios and the As-Co-Ni ternary diagram of pyrite indicate that the genesis of pyrite in the Lianhuashan gold deposit is relatively complex, constrained by multiple factors including the Jianping Group, regional metamorphism, and magmatic hydrothermal activity. The characteristic values of Au/Ag and S/Se ratios in pyrite display magmatic hydrothermal signatures, suggesting that the formation of ore-forming fluids was primarily related to magmatic activity in the mining area. The w(Fe)/w(S+As) ratio, comprehensive pyrite trace element ratio H, and trace element assemblage distribution diagram reveal favorable prospecting potential at greater depths. Combined with ore-controlling structural analysis, it is inferred that a high-grade orebody may exist within a 200-meter downward extension of Vein No.51.