Some discrimination criterions of W/Sn mineralization re-lated granitoids in Nanling Range

Most tungsten-tin polymetallic deposits are undoubtedly coexist with intermediate-acid granitoids in Nanling Range, South China. This paper focus on the field identifications of granitoids related to W/Sn mineral-ization. In the discrimination process, granitoids related to W/Sn mineralization are firstly differentiated from those unmineralized, and further divided into W series and Sn series from each other. Compared to those unmineralized granitoids, the majority of mineralized granitoids have positive W, Sn, F, B geochemical anomaly, multiple litholo-gies and appropriate tectonic superposition (or hydrothermal alteration). Granitoids unmineralized can be easily i-dentified by W, Sn, F, B background contents, simple lithology, lackness of late granitic stocks/veins and alter-ations. In field exploration, Sn series are easily indentified by granodiorite-monzogranite-two-mica granite lithologies, widespread MME and hornblend in basic end member with higher biotite content (4-6 wt% or higher), and low muscovite content (<1 wt%) in acid end member. While W series can be differed from Sn series by sev-eral other features such as monzogranite-two mica granite-muscovite granite lithologies, biotite noddle, meta-sedimentary and hostrock enclave commonly seen in basic end member with lower biotite content(2-4 wt%) and little hornblend, and identical disseminated tourmaline and high muscovite content (1-2 wt%) in acid mem-bers.