Abstract: As the common sulfide mineral in metallic mineral deposits, the molybdenite has played an important role on the isotopic dating of the deposit. Besides the widely application of Re-Os method of isotopic dating, the new application of this mineral on the REE (rare earth elements) geochemical study is reported in this paper. Based on the studies of 14 Mesozoic W, Mo and poly-metallic ore deposits from Hunan, Jiangxi and Fujian Province, it’s a fact that the REE contents and normalized pattern of molybdenite samples from different types of deposits are different from each other. Although these differences are resulted from multi-causes, such general features of REE content, ratios and chondrite-normalized patterns can be outlined as followings:1)different types of ore deposits have different REE geochemical features. For example, porphyry Cu-Mo deposits, hydrothermal Mo deposits hosted within volcanic rocks and hydrothermal W deposits originated from granite can be distinguished by REE features of the molybdenite;2)different deposits belonging to the same type and with the same mineral resources have similar REE features, no matter what geological settings they are located in. The tungsten deposits in Southern Hunan have similar REE features, recorded in the molybdenite, as those in South Jiangxi;3)the molybdenite formed at different stages have different REE geochemical features, but those formed at the same stage and in the same geological environment might have similar features. For instance, all of the studied middle-later Jurassic molybdenites construct a trend of gradually increasing of ∑Ce/∑Y ratio with ages;4)because the molybdenite formed at different settings can have similar feature, while those formed at the same metallogenic belt might have different features, the conclusion is that the ore-forming tectonic settings cannot be discriminated only by REE geochemistry of molybdenite;5)the comparison of the molybdenite from different mines can provide valuable information for mineral exploration. Although the tracing of REE in the molybdenite is preliminary and is to be further studied, it provides a new method for studying the genesis of the ore deposit.

Key words: molybdenite, Rhenium-Osmium age, mineralization, REE elements, geochmistry