Several vein- like silver polymetallic deposits are developed in Luoning County, western Henan Province, China. Among these, the Shagou deposit, characterized by significant Ag- Pb- Zn mineralization, commonly contains authigenic quartz grains coeval with sulfides.These quartz grains provide valuable insights into the physicochemical conditions prevailing during different mineralization stages and the precipitation mechanisms of metal minerals from ore- forming fluids. This study presents a detailed mineralogical investigation of quartz in the Shagou deposit, utilizing cathodoluminescence (CL) imaging, fluid inclusion microcalorimetry, and individual fluid inclusion composition analysis. These techniques were applied in conjunction with detailed field geological investigations. The mineralization process of the Shagou deposit comprises three stages: a quartz- siderite- pyrite stage, a quartz- dolomite- polymetallic sulfide stage, and a quartz- calcite stage. In the quartz- dolomite- polymetallic sulfide stage, three generations of quartz were identified: ① Q1, located in the core of quartz grains, exhibits uniform bright CL intensity with undeveloped growth zonings; ② Q2, found in the mantle of quartz grains and coeval with sulfides, is characterized by dark CL intensity and chaotic growth zonings; ③ Q3, situated at the edge of quartz grains, displays bright CL intensity with well- defined growth rings. Compositional analysis of quartz from various generations revealed a strong positive correlation between Al and Li content (R2 = 0.97) across all stages. This correlation is closely linked to CL brightness, indicating that Al3+ and Li+ substitute for Si4+ within the quartz structure. Ti content in Q1 and Q2 ranges from 0.722×10-6 to 3.62×10-6 and 0.387×10-6 to 1.12×10-6, respectively, while Al content ranges from 81.9×10-6 to 2436×10-6 and 3.67×10-6 to 132×10-6, indicating a medium- low temperature hydrothermal environment for mineralization, with decreasing temperature and increasing pH as the primary factors triggering mineral precipitation. LA- ICP- MS analysis of single fluid inclusions showed enrichment in alkali metals with high Rb/Na and Cs/Na ratios. This strongly suggests a magmatic origin for the mineralizing fluid, classifying the Shagou deposit as a magmatic- hydrothermal mineralization system.