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Geochemical and mineralogical investigation on both mineralized and non-mineralized psammitic gneisses were carried out on surface and core samples from Wadi Abu-Rusheid, Eastern Desert, Egypt. Chemical analyses indicated that significant enrichment of Zr, Nb, Pb, Zn, Sn, Y, Cu and Li are confined to the upper zone of the mineralized psammitic gneiss. Both the upper and lower zones are greatly contrasted in their accessory minerals, being composed of Li-mica, bipyramidal zircon, columbite, cassiterite, thorite, fluorite and some sulphides in the upper zone, while mica, fluorite and long prismatic zircon characterize the lower zone.

The model suggested for the re-distribution of the rare elements assumes that these elements have been squeezed out from lower horizons, were carried upwards with the fugitives, and deposited during one or more phases of neo-mineralization. Accordingly, these rare elements were present in the original rocks prior to metamorphism.