Gebel El Nekeiba is composed mainly of quartz-syenite surrounding syenogranite. Syenogranite is
characterized by the presence of allanite, zircon and fluorite. Qz-syenite is more radioactive and characterized
by the presence of violet and deep violet fluorite, zircon and columbite besides thorium minerals (thorite and
orangite). The latter were transformed to thorogummite by hydrolysis. The studied rocks are characterized
by low Th/U ratio. Quartz syenite and syenogranite rocks show high concentrations of REEs; the former is
characterized by higher concentration of HREEs than LREEs. Distribution of REEs in Gebel El Nekeiba
is controlled by the elements concentration in the parent magma, and degree of fractionation in the hosting
rocks and minerals.