Skarn and porphyry type copper-polymetallic deposit in the central part of the Baoshan ore field.

Cu polymetallic mineralization in BS pluton is associated with granodioritic porphyry, with a total metal reserves of 0.24 Mt at an average grade of 1.28 % Cu, 0.47 Mt at an average grade of 3.82 % Pb, 0.51 Mt at an average grade of 4.34 % Zn, and 0.012 Mt an average grade of 0.12 % Mo. The mineralized granodioritic porphyry is also the dominated igneous rocks exposed in this area, which has a gray color, and massive and porphyritic structure. Two-type orebodies (skarn Cu and metasomatic Pb-Zn-Ag) occur in stratiform bedded, veined, and lenticular, which are genetically related to the granodiorite porphyry.

Cu 238,700 t @ 1.28%; Pb 470,700 t 3.82%, Zn 512,800 t 4.34%; Mo 11,700 t

The Baoshan deposit exhibits intense hydrothermal alteration, mainly including potassic alteration, silicification, sericitization, skarnization, carbonatization, and fluoritization, among which skarnization, silicification, fluorization, and carbonatization are most closely related to mineralization.

The exposed stratigraphy mainly included the Upper Devonian Xikuangshan Formation (D3x); the Lower Carboniferous Menggongao (C1m), Shidengzi (C1sh), Ceshui (C1c), Zimenqiao Formations (C1z); and the Middle–Upper Carboniferous Hutian Group (C2+3h). The Lower Carboniferous Shidengzi limestone, Ceshui quartz siltstone, carbonaceous shale and Zimenqiao dolomite are the main ore-bearing wall rocks in the Baoshan mining area. The orebodies are produced in veins and have a lamellar or lenticular shape. The contact boundary with the skarn is clear. The central Cu orebody is mainly stratiform, vein, lentil or lens-like, with a continuous distribution, a large scale and a high grade of orebodies, which are closely related to skarn and are obviously controlled by the Baoling inverted anticline. The western and northern Pb-Zn sections are dominated by hydrothermal and metasomatic vein-filling, stratified and lenticular-shaped Pb-Zn mineralization. The orebodies are mainly located in the fracture zone (F21 and F25) and the interlayer fracture zone of the fault footwall, and a small amount is located in the southern flank of the Baoling inverted anticline.
Tthe Baoshan Cu-Pb-Zn polymetallic deposit can be divided into four ore-forming stages. (1) In the early skarn stage (S1), early anhydrous skarn minerals such as garnet and diopside are mainly formed, and radial and clustered wollastonite are rare. (2) The late skarn stage (S2) is manifested by the degeneration of early skarn minerals, mainly forming epidote, actinolite, chlorite and other minerals, and a disseminated scheelite formation is locally visible. At this stage, quartz veins began to form. Small amounts of pyrite and magnetite were precipitated in the late stage, and the scheelite particles formed in the early stage were cut and replaced. (3) In the Cu-Fe sulfide stage (S3), which is the main ore-forming stage of the central Cu section, a large amount of chalcopyrite, pyrite and molybdenite precipitation is characteristic. Moreover, a small amount of sphalerite can be observed, which is closely related to chalcopyrite. (4) The Pb-Zn sulfide stage (S4) is another main metallogenic stage of the western and northern Pb-Zn sections. At this stage, the pyrite–sphalerite–galenite–quartz (±fluorite) veins can be seen in the early stage, and the pyrite–sphalerite–galenite–calcite (±fluorite) veins dominate in the late stage. In sulfide ores, pyrite, sphalerite and galena are deposited and replaced in turn.

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