The Danchi fold-and-thrust belt, Guangxi, South China, contains the Mangchang, Dachang, and Wuxu large and giant Sn-polymetallic districts. It hosts more than 1.2 Mt of ore grading 1 % Sn, 6.23 Mt Zn at 2.4 %, and 1.13 Mt Sb at 1.3 %. Wuxu district is one of the Sb-Zn dominated hydrothermal districts without magmatic rocks exposing in the south of the Danchi belt. Recent drilling and exploring mining have identified a partially Sn mineralization associated with the Zn-Sb mineralization. These works provide an opportunity to evaluate the potential of tin mineralization in the south of Danchi belt and relationship among Sn, Zn, and Sb mineralization. Structural analysis suggests that the Wuxu district underwent at least three deformational phases since the Triassic. The first NE-SW shortening deformation controlled the structural framework of the Wuxu district and is expressed by NWverging thrusts and folds, axial-plane cleavages around the core of the Wuxu anticline, transverse joint sets on the limbs of the Wuxu anticline, and dilational zones in the bedding-fractures. Afterward, an E-W extension stress field produced NS-striking normal faults and reactivated pre-existing NNW-striking faults which were expressed by sinistral top-to-the north sense of shear. During this deformation, some low order dilational spaces of the NWstriking faults and bedding-fractures formed and a syn-kinematic deposition of minerals in these hosting structures to form the ore shoots. The NNW-striking faults, axial-plane cleavages, and large dilational jogs controlled the subvertical large veins in the Jianzhupo deposit. The conjugate joints and inter-bedding fractures in the limb of the Wuxu anticlinorium controlled the branching veinlets and stratiform, paleokarst infilled ores in the Bawang deposit. The post-ore EW-striking faults are not obvious and displaced preceding two-phase structures and ores. Three primary paragenetic stages of hydrothermal process have been recognized: (I) Sphalerite dominated + massive pyrrhotite with euhedral pyrite porphyroblasts, (II) Cassiterite + siderite + arsenopyrite dominated with minor scheelite + quartz + fluorite, and (III) Jamesonite + stibnite + sulfosalt + carbonates. Cassiterite U-Pb dating provided a lower intercept age of 90.2 +/- 3.1 Ma and 90.6 +/- 4.6 Ma for the Jianzhupo and Bawang deposits, respectively. These two ages are consistent with the chronological data of tin-sulfides and orerelated felsic intrusions in the Danchi fold-and-thrust belt, South China. Our studies coupled with previous gravity data suggests a distal magmatic-hydrothermal infilling tin-polymetallic district and indicates that the Wuxu district has great potential for additional tin mineralization.

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