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Association of titanium-zirconium placers and phosphate mineralization in Upper Cretaceous rocks of the East European Platform is shown with the Tsentral’noe (Central) and Unecha deposits as example. This paragenesis is caused by interaction between the multicomponent placer ore (phosphate-rare metal) concentrations and mechanical-chemical differentiation that shows up periodically during the sub-aerial migration of sedimentary material. Clastic ore components were mainly derived from intermediate collectors, while the phosphate material was delivered by the phosphate-containing solutions and particulates in the chemical weathering crust. Such phosphorite-titanium-zirconium occurrences can also be detected in other regions, including areas with rare metal placers.

Lithofacies analyses and paleogeographic reconstructions of the middle Sarmatian sequence in the central Ciscaucasus, which hosts the most promising titanium–zirconium placers of the Stavropol region, indicate that ore components (rutile, ilmenite, leucoxene, and zircon) were mainly delivered to the Stavropol placer basin by the paleo-Volga River from a northern land. Bryozoan organogenic edifices played a significant role in the formation of placers. The organogenic edifices appeared under anomalous (for bioherm formation) conditions of terrigenous sedimentation on the western and northwestern slopes of the Stavropol Uplift, hampered the transport of ore material to the deep-water zone of the basin, and promoted its differentiation in the paleouplift.

The lithofacies features and formation conditions of Meotian rocks in the Azov–Kuban region are defined. It is shown that the bryozoan organogenic buildups were formed in the Enikale (Kerch) Strait, as well as in the littoral–shallow-water areas of the sedimentary basin. Currents flowing from the Azov–Kuban Sea favored an intense bioherm formation in the paleostrait. They provided the optimal hydrodynamic regime for this process and supplied bryozoans with the needed nutrient medium. The obtained data can be used for estimating the metallogenic potential of Meotian reefal deposits in the Azov–Kuban region.