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The Genina Gharbia intrusion is a small late Precambrian mafic-ultramafic complex in the Eastern Desert of Egypt. It comprises harzburgite, lherzolite, pyroxenite, norite and gabbro. The intrusion is not metamorphosed. but highly affected by faulting and shearing. and most of the original contacts have been obliterated. The various rocks are characterized by high modal content of magnesia hornblende and abundant phlogopite and fluorapatite. The Cu-Ni ore forms either disseminations in peridotite or massive patches in gabbro and consists of pyrrhotite >> pentlandite = chalcopyrite >> pyrite = violarite = cubanite and minor cobaltite-gersdorffite, nickeline, sphalerite, molybdenite and valleriite. Intense alteration commonly is associated with sulfides in gabbroic rocks. in which the silicate assemblage is dominated by actinolite, chlorite, epidote, albite and quartz. Platinum-group minerals (PGM) are restricted to bismuthotellurides of Pd, i.e., michenerite and the melonite-merenskyite series: no Pt minerals were identified. The PGM are Usually associated with hessite, altaite, tsumoite, sylvanite and native tellurium. Ninety percent of the PGM and other tellurides grains are located at sulfide-silicate contacts and as inclusions in altered silicates. The total Cu + Ni locally reaches up to 1.5 wt%, with it Cu:Ni ratio < 1. Platinum-group elements (PGE) concentrations (maximum 260 ppb Pd, 65 ppb Pt 9 ppb Rh 38 ppb Ir. 10 ppb Ru. 7 ppb Os) were determined in sulfide-bearing samples. The Pd:Pt ratio increases from the hornblende harzburgite to hornblende gabbro. The mineralogical and chemical characteristics of the Genina Gharbia mineralization are best explained by a three-stage process: (1) a stage of magmatic crystallization in which the base metals and precious metals were concentrated in it Sulfide melt largely in the harzburgite and lherzolite, (2) a late-magmatic stage in which base metals and precious metals were concentrated in a volatile-rich fluid, and (3) a postmagmatic stage of faulting and shearing, which locally remobilized metals and concentrated them along shear zones. In stage (1), the PGE were hosted in base-metal sulfides, mainly pentlandite and cobaltite-gersdorffite. The availability of semimetals (Te, Bi) in the late-magmatic fluid controlled the deposition of PGM in stage (2).