The Tumen fluorite-Mo deposit, Fangcheng County, Henan province, occurs in southeastern Huaxiong Terrane which is north of the regional Luanchuan fault. Hosted by inter-bed fractures between marble and schist, orebodies are strata-bound lodes and lens occurred in the outer contact zone of granite porphyry and host-rocks of reversal wing of a geosyncline. Main minerals of ores include luorite, sulfides and carbonate. According to the crosscutting relations of veins and ore textures and structures, hydrothermal ore-form ng process are divided into four stages characterized by mineral assemblages of (I) white fluorite, (II) Mo-bearing purple fluorite, III) polymetallic sulfides, and (IV) carbonates, respectively. Fluid inclusions include four compositional types: NaCl-H2O (W-type), (CO2-H2O-NaCl (C-type), pure CO2 (PC-type) and daughter crystal bearing (S-type). Microthermometry in fluid inclusions in fluories shows that the homogeneous temperatures of stage I range from 300 similar to 420 degrees C, with majority of 360 similar to 410 degrees C; and those of stage II, range from 180 similar to 380 degrees C with majority of 220 similar to 300 degrees C. In correspondence, The fluid inclusion salinities of stage I are up to 49.68 wt% NaCl eqv., whereas those of stage II are no higher than 13.07 wt% NaCl eqv.,. From early to late stages, the densities of W-type inclusions decrease from 0.88 to 0.84g/cm(3), and the densities of CO2 in C-type inclusions increase from 0.66 to 0.82 g/cm(3). In general the Tuman Mo deposit has been formed by a medima-to-high temperature, high salinity and high-contents of CO2 and F fluid-system, and is genetically attributed to intrusion-related vein type hydrothermal system developed in intra-continental setting.
