The Dariyati granite, quarried for the use as a facade for the Holy Mosques in Makkah and AI-Madinah, belongs to the late-stage plutonics of the Arabian Shield (585 ± 8 Ma). It is a typicalleucocratic equigranular coarse-grained 'trans-solvus' granite formed dominantly of perthite, both orthoclase and microcline, quartz and 9ligoclase. Plagioclase crystallized first followed by potash feldspar then quartz. The granite is slightly peraluminous with low Ca, Mg, Fe and Ti contents. Its Ab-Qz-Or composition indicates a near minimum melt potassic granite'. Compared to average abundance of granites, it is significantly depleted in the incompatible elements Ba, Sr, Zr, Ce, La, Y, and Nd. Thronton-Tuttle indices as well as RblSr and KlRb ratios suggest fairly evolved stage of differentiation. The initial 87Sr/86Sr ratio (0.7037 ± 0.0003) suggests derivation from mantle source with limited crustal contamination or by low degree partial melting of the lower cru:st. Petrochemical and geochemical features however, support a crustal melt origin.