Ore-forming material of Dachang tin deposit in Guangxi, China: Lead isotope evidence

For revealing the ore sources of the Dachang tin–polymetallic ore deposit, the lead isotopes were analyzed systematically by using the single minerals of sulphides, including pyrite, pyrrhotite, sphalerite, and galena. Then, the mineral sources and their characteristics were discussed based on the classical lead isotope discriminating model. The results show that the lead isotope ratios of 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb range from 17.478 to 18.638, 15.440 to 15.858, and 37.556 to 39.501, respectively. According to Zartman lead model, the ore lead contains the upper crust composition; however, the granite does not provide all ore leads, and other material sources exist. Obviously, the ore deposit belongs to the result of the combined effect of crust–mantle. The source rocks are characterized by a certain degree of similarity with the island arc material. Moreover, its distant origin in the upper and lower crusts 5 be related to the subduction island arc material or oceanic crust. The mantle-derived material 5 have a certain status in the source region. Meanwhile, based on the lead isotope three-dimensional topology projection vectors, the ore leads are concentrated in zone A, which indicates the characteristics of Yangtze lead isotope province and a possible genetic relationship with Yangtze block.