Abstract:The Jilongshan Au deposit is a typical skarn deposit in southeastern Hubei Province, but its skarn mineralogy research is insufficient. The Jilongshan skarn Au deposit is exposed within the dolomitic limestone of Triassic Daye Formation and the Yanshanian granodiorite porphyry. The metal minerals mainly include natural gold, chalcopyrite, pyrite, molybdenite, bornite, sphalerite, galena, orpiment, realgar, and magnetite, whereas the skarn minerals are mainly garnet, diopside, epidote, wollastonite and phlogopite. The authors studied in detail the skarn mineralogical characteristics of different stages and conducted the electron microprobe analysis (EMPA). The results show that the garnet belongs to the calcium And-Gro series, the pyroxene is diopside, and the calcium-iron garnet-diopside gold-rich skarn combination was formed under the condition of high oxygen fugacity and relatively low acidity, with copper, gold metallogenic specialization. Along with the fluid evolu- tion, ore is associated with skarn in space, time and origin. In combination with the development of the porphyry ore body, the authors hold that the Jilongshan gold deposit may have a unified porphyry-skarn mineralization system, and there exists great prospecting potential in the depth.