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Three distinctive metaluminous granitic suites have been identified from the Pan-African belt of the Kab Amiri area, Eastern Desert, Egypt. These are: 1) a trondhjemitetonalite suite, 2) a calc-alkaline granodiorite suite, and 3) an alkali leucogranite suite. The trondhjemite-tonalite and the granodiorite suites resemble I-type granitoids whereas the alkali leucogranites display A-type characteristics. Geochemical attributes and field aspects indicate that three independent magmas, at different tectonic stages of the Pan-African crustal growth, are required to explain the origin of these granitoid suites. Rocks of the trondhjemite-tonalite suite correspond to granites of the arc stage and possess a narrow range Of SiO2 with low K2O, Sr, Rb, Ba, Nb and Zr. Its composition is consistent with 20-30% partial melting of a primitive low-K tholeiitic source, similar to the early formed tholeiitic metavolcanics of the Egyptian basement. The granodiorite suite belongs to the collision stage and displays higher K2O, Rb, Ba, and Sr. Its magma was derived by 30-40% partial melting of LILE-enriched mafic island arc crust. The presence of abundant microdiorite enclaves in the trondhjemite-tonalite and the granodiorite suites suggests that mantle-derived mafic magma played an important role in their petrogenesis, acting as a heat source for melting via underplating and/or intrusion. The A-type leucogranites are post-collision highly fractionated granites. They exhibit low Al2O3, MgO, CaO, TiO2, Sr, and Ba and high Rb, Nb, Y The wide chemical variations within this suite are consistent with its evolution by fractional crystallization of plagioclase, K-feldspar, amphibole, Fe-Ti oxides, and apatite from a mafic magma. The parent magma was originated in the upper mantle due to crustal attenuation associated with extension in the late stage of the Pan-African crustal evolution.