Fluids are major fractionation agents in granitic systems because they partly control the behaviour and partitioning of elements, including rare metal, during the magmatic-hydrothermal transition and their subsequent redistribution during the later subsolidus stage. The exsolution of magmatic fluids from a volatile-saturated magma and their subsequent circulation commonly result in important textural and geochemical changes with primary magmatic features being entirely overprinted and earlier minerals chemically re-equilibrated. The changes documented herein serve as a basis for tracking the equilibration of a rare-metal granite with interacting fluids. The Mueilha F-Nb-Ta-REE-Y granitic system (Eastern Desert of Egypt) is composed of different facies such as the “red granite”, representing the main volume of the intrusion, and the “border facies”, occurring along the red granite south-western margin