| Western Guangxi lies in the southeast Diwa zone, between Gong-Gui Diwa system and Dian-Gui Diwa system, where folds and faults war developed very well. In this region, aluminum resources are very rich, Al-polymetal deposits are distributed in the ancient Daxin dissolved plain such as Pingguo, Jingxi, Debao, and Tiandong and so on . According to the genesis of these ore deposits, they can be divided in two types: one type is sedimentary deposit, the other is accumnlated Al-polymetal deposit, the first is occurring on the erosion surface of early Permian Maokou limestone - the bottom of late Permian rocks of Heshang group with coal bed and pyrite deposit together as bedlike or bedway, which is not utilized at present because of the high content of S. The other Al-polymetal deposit is occurring in the red soil bed of Quaternary, featuring shallow buried, wide distribution, high A/S and good quality, which is being mostly utilized at present.The chemistry components have not obvious difference between the two types of Al-polymetal ore except the content of S, both of them consist much of Al2O3, Fe2O3, SiO2, TiO2 , H2O+and some of Ga, V2O5, Sc, Nb, Ta, rare earth elements and so on .They almost consist of the same minerals between the two kinds of Al-polymetal deposit ores except the content of pyrite is relatively high and the limonite and pin-iron ore are relatively low in the sedimentary Al-polymetal ores.In the mud of Debao Longhua Al-polymetal deposit, an unknown mineral is determined as Beidellite using way of XRD and Greene-Kelly, the content of this kind of mineral is 15.45% by way of montmorillonite group quantitative analysis .In 1980's, a new analytical technique--Inductively coupledplasma mass spectrometry (ICP-MS) was introduced to the marketplace, the success of ICP-MS as analytical techniques stems mainly from the following important capabilities: very low detection limits (10"12), broad dynamic concentration ranges (8-11 orders of magnitude for many elements), simple mass spectra, few spectral interferences, good precision,ability to routinely provide elemental isotopic information, and so on. A sets of feasible ICP-MS analytical technique for trace element in western-Guangxi Al-polymetal ores have been developed in this paper.The content of gallium is relatively high, it distributes in all sorts of Al-polymetal ores almost at all as isomorphism with aluminum, and which has good correlation with aluminum.The content of rare earth elements (REE) are relatively high. It is known that the REE distribute in diaspore crystal lattice as nano- meter mineral matters and prominent positive correlation with AI2O3 by ICP-MS analytical technique based on analytical chemistry and mineralogy analytis. There have some different between sedimentary and accumnlated deposit about the content and distribution pattern of REE too.The geochemistry feature of REE; B, Be, Sr/Ba, Th/U, sulfur isotopes, noble metals, the ratio feature between Zr, Hf, Nb, Ta, TiO2 and Al2O3, the triangle diagrammatize feature of Zr, Cr, Ga, and the ore-bearing profil and distribution features show that:(1) the ore-forming materials of the Al-polymetal deposit mostly origin from Maokou limestones in the paleoweathering crustal basement and Daxin paleocontinental rocks, some from eruption and so on.(2) the deposit Al-polymetals which are marine environmental clastic deposits.(3) the accumnlated Al-polymetals anormaly result from the physical , chemical and biological weathering processes of the primary Al-polymetals under the hydrogenic environment duing the Dewa stage.(4) Organism and the derived materials played roles in different stages of the Al-polymetal metal-logenesis, such as weathering, eluviating, transportation, organic material protected gel, the absorption, resolution and purification of large amount of orgrnic matter in water of sedimentary basin in which syngenetic and diagenetic stages were under reduction and diaspore and pyrite formed. In the supergenetic stage the oxidation of organic mat...
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