摘要：The Ijebu-Ife study area is located between longitude E4000’– 4003’E and latitude N7053’- 7056’N of Ibadan Sheet 261 S.E. Precambrian pegmatites occurring as near vertical dykes and striking mainly in the NNE-SSW direction have been studied in Ijebu-Ife area with a view to elucidate their Geochemical characteristics and possible economic potentials. These pegmatites intrude into the older lithology of biotite granite around Ijebu-Ife area Southwestern Nigeria. Three thin sections were prepared from the pegmatites of the study area for Petrographic study . A total of ten samples comprising muscovite extracts from pegmatites of Ijebu-Ife were analyzed for major and trace elements using Inductively Coupled Plasma-Atomic Emission Spectrometry analytical technique (ICP-AES). Petrographic study shows that quartz, muscovite, microcline, plagioclase and biotite are the main mineral constituents under the transmitted light. From the geochemical results, the whole rock pegmatite is considerably siliceous, with an average value of 65.98%, while, MnO with a range of (0.03-0.11%), TiO2 with a range of (0.94-4.82%), P2O5 with a range of (0.03-0.27%) hasvalues that are generally low. Mean contents of major oxides, Al2O3 (7.176% ), Na2O (1.89%), Fe2O3 ( 19.289%), MgO (0.049%), CaO (0.30%), and K2O (1.86%) for the Ijebu-Ife pegmatites compare favorably with the Ipetu-Ijesha barren pegmatites , Kafin-Maiyaki barren pegmatites and Ago-Iwoye barren pegmatites. Ijebu-Ife pegmatites are fairly enriched in Rb, Sr, Zr but comparatively, poor in the rare metals Ta, Nb,,Cs and Sn. Rare metal mineralization enrichment indices mainly, Ta vs Nb, Ta vs K/Cs, plots, show its depletion in rare metal mineralization, suggesting thispegmatites to be barren in rare-metal mineralization when compared with other rare-metal pegmatites across the world.
