Abstract Fe-Ti vanadium placer ore deposit of Rivash with thousands tons of ore grading up to 63%. Fe, 6.8 TiO2 and more than 10000 ppm Vanadium is located at the north margin of the Darouneh great Fault. The Titanium and vanadium mineralization in the area is originated from ophiolitic complex of cretaceous age which consist of peridotites (dunite, lherzolite) and serpentinized peridotites, gabbros, sheeted dikes, pillow and massive lava. The hydrothermal alteration of the host rocks can be recognized by a distinct colour change at the surface of the field and is distinguished by serpentinization and rodingitization zones. The main ore zones (titaniferous magnetite and magnetite) contain elevated abundances of Fe > Ti > Cr > V. The geochemical studies showed higher anomalies of Fe in the southern part of the area, while with increasing V, an elevated trend of Ti, and Fe elements were observed in the area of the study. The source of ore metals can be attributed to the magamtic activities and host rocks which were leached by water-rock interaction during the hydrothermal circulation of fluids in the system. The mineralogy of the placers are simple, with only trace impurities, and magnetite constituting about 95% of metallic minerals in the area of the study. Other sulphide minerals present are pyrite and chalcopyrite. The ore deposit originated from intrusive complexes which typically were emplaced at deeper levels in the crust. Progressive differentiation of liquids residual from gabbroic magma leads to late enrichment in Fe and Ti. Typically plagioclase crystallization results in concentration of Fe and Ti in residual magmas which typically crystallize to form ferrogabbros. Layers form by crystal settling and accumulation on the floors of magma chambers and the disseminated deposits are believed to have formed in-situ. Two genetic models have been suggested, remobilization of the crystal cummulates into cracks or fractures or emplacement as Fe-Ti-oxide-rich immiscible melt with little silica. The key control was the development of a late, separate Ti and Fe-rich liquid from a fractionating magma under stable conditions. The deposit occured in elongate belts of intrusive complexes emplaced along deep-seated faults and fractures.

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