A preliminary geological and geochemical study of the Xiangquan thallium deposit, eastern China: the world';s first thallium-only mine

作者:Zhou TF*; Fan Y; Yuan F; Wu MA; Hou MJ; Voicu G; Hu QH; Zhang QM; Yue SC
来源:Mineralogy and Petrology, 2005, 85(3-4): 243-251.
DOI:10.1007/s00710-005-0088-2

摘要

Here we report the first example of a thallium-only deposit, which was discovered in the northeast margin of the Yangtze block, eastern China, in the transition zone between the Yangtze Block, North China Block and Dabie orogenic belt. Ore from the Xiangquan deposit will be mined, ore-dressed and smelted independently for thallium. The ore deposit is hosted in Lower Ordovician micrite, calcilutite and marl within the Dalongwang Mountain Xiao Mountain anticline. The ore zones are fold and fault controlled. Thallium occurs mainly in pyrite but minor amounts form as lorandite (TlAsS2) and hutchinsonite (TlFeS2). Fluid inclusion studies of two stages of fluorite intimately associated with ore-forming pyrite yielded homogenization temperatures of 120 to 220 degrees C with a salinity of 1.5 to 6.0 equivalent wt.% NaCl. Thallium was originally derived by hydrothermal emanations onto the sea floor and deposited in calcareous sediments. Subsequently in the Early Cretaceous (Yanshanian period) these source beds were reworked to form thallium enriched minerals in hydrothermal veins.