The strata outcropping in the Banxi Sb deposit mainly consist of the Wuqiangxi Formation of the Banxi Group with a Neoproterozoic age, which contains regional low-grade metamorphic clastic rocks with original characteristics of a littoral facies-neritic facies flysch sedimentary sequence. Six ore veins have been discovered in the Banxi deposit which are mainly hosted in the cores of anticlines and are strictly controlled by faults. The Banxi Sb deposit (>100,000 t Sb metal with a grade of 0.02%–64.5% Sb (typically 15.3%–25.9% Sb) in the Eastern Yangtze Block is hosted in Neoproterozoic low-grade metamorphic clastic rocks of the Banxi Group.

The Banxi Sb deposit is divided into three mineralization stages: the quartz stage (dominated by massive quartz), the quartz-stibnite stage (mainly consisting of quartz and stibnite, with minor amounts of pyrite), and stibnite stage. Most of the quartz-stibnite veins in the second stage are parallel to the quartz veins formed during the first stage, while a small amount of the second-stage quartz-stibnite veins cut across the first stage quartz veins in a reticular vein cutting pattern. The stibnite stage represents the main mineralization stage, during which stibnite veins cut through the quartz-stibnite veins of the second stage.

The exposed strata in the Banxi area belong to the Wuqiangxi Formation, a suite of weakly metamorphosed clastic rocks that preserve the primary features of a shoreface–shallow-marine flysch sequence. The formation can be further subdivided into three members from the bottom upward. The first member, located in the core of the Jiangjiazhong Anticline, consists of gray-green metamorphosed tuffaceous sedimentary rocks, tuffaceous siltstone, tuffaceous slate, sericite slate, and sandy slate, with occasional interlayers of feldspathic quartz sandstone. The second member, exposed along the limbs of the Jiangjiazhong Anticline, comprises thick-bedded tuff, tuffaceous slate, sericite slate, and tuffaceous sericite slate. The third member is composed of silty slate, purplish-red slate, banded slate, sericite slate, and silty sericite slate. The lower section is dominated by tuffaceous slate, the middle section by metamorphosed tuff, and the upper section by metamorphosed sandstones. Among the numerous antimony veins in the Jiangjiazhong Anticline area, only Vein No. 2 has been exploited, making it the largest and most economically significant vein. In plan view, the vein exhibits an elongated S-shaped geometry and extends for more than 1,000 m. In cross-section, the vein comprises three segmented and discontinuous ore bodies (2–1, 2–2, and 2–3) that extend from NE to SW and exhibit left-lateral displacement. The strike of Vein No. 2 varies significantly (45°–80°), as does its dip angle (45°–89°), with a typical vein thickness of 0.3–1 m. , the mineralization at Banxi can be subdivided into four distinct stages.: (1) the quartz stage, (2) the quartz–sulfide stage, (3) the stibnite–quartz stage, and (4) the carbonate stage. Among these, the stibnite–quartz stage is the most significant and well-developed mineralization phase. Wall-rock alteration includes silicification, chloritization, pyritization, arsenopyritization, and sericitization.

Other Regions, Features and Areas containing this locality

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