Application of X-ray Fluorescence Spectrometry and Inductively Coupled Plasma-Mass Spectrometry in the Geochemical Study of Rare Metal Deposits in Chuan-ziyuan Area, Hunan Province

X-ray Fluorescence Spectrometry (XRF) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) were used to obtain the geochemical data of podumene pegmatite, albite pegmatite and potash feldspar pegmatite in the Chuan-ziyuan area. Podumene pegmatite contains high Al₂O₃ (16.23%-16.4%) and K₂O (3.05%-5.22%) with high differentiation index (91.13-94.9). Podumene pegmatite is enriched in Rb and K but depleted in Ba, Sr and Ti with ΣREEs of 2.9×10^-6-3.5×10^-6. Albite pegmatite is characterized by high Na₂O (5.58%-7.41%) and low K₂O (0.98%-2.62%). Compared to podumene pegmatite, the Rb/Sr ratios of albite pegmatite decreased and REEs increased. Potash feldspar pegmatite contains high K₂O (9.13%) and low Na₂O (1.69%), the Zr/Hf and K/Rb ratios increased compared to podumene pegmatite and albite pegmatite. The geochemical characteristics of these rocks indicate that liquid immiscibility, albitization metasomatism and potash feldspathization metasomatism resulted in Li and Rb mineralization in podumene pegmatite, Nb, Ta and Be mineralization in albite pegmatite and potash feldspar pegmatite, respectively. These observations are geochemical indicators for exploration of the rare metal deposits.