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Data on the concentration of rare and rare-earth elements in the Devonian manganese-rich metasediments of the Polar Urals and Pai-Khoi Ridge are presented. It is shown that Sc, V, Rb, Zr, Nb, Hf, Th, and U represent elements delivered to the metalliferous sediments as a part of the detrital material. Excess (relative to the background detrital material) concentrations are established for Li, Be, Cr, Co, Ni, Zn, Ge, As, Mo, Sb, W, and Pb. They could be delivered from a specific detrital or chemical material (for example, ferruginous), seawaters (hydrogenic sorption of elements), biogenic substance (carbonate, siliceous, phosphate, carbonaceous), diagenetic interstitial pore waters, and hydrothermal solutions. In terms of the concentration of rare-earth elements, the studied rocks are comparable to the present-day diagenetic ferromanganese deposits.

A variety of caryopilite enriched in Mg and Al from the goethite–neotocite–rhodochrosite ores of the Mazul manganese deposit in Krasnoyarsk Krai is described. The mineral occurs as sheaf-like and fibrous aggregates of fine-lamellar individuals intimately intergrown with goethite, hematite, rhodochrosite, and neotocite. The optical parameters of caryopilite are: Z = yellow, X = pale yellow, β ≈ 1.60, γ – α ≈ 0.010 – 0.015, and parallel extinction. The average chemical composition corresponds to the empirical formula (Mn1.95Mg1.61$${\text{Fe}}_{{0.63}}^{{2 + }}$$Al0.58◻0.23)5.00[(Si3.88Al0.12)4.00O10](OH)6, where ◻ is vacancy. The unusually high Mg concentration and elevated Al content allow identification of a new aluminum–magnesium variety of caryopilite. It replaces sedimentary neotocite at low temperatures. It is suggested that at increasing temperature this variety of caryopilite loses Mg and Al, which incorporate into Mg–Mn chlorite and spessartine.

Gallium-containing chlorite, mica, and magnetite (up to 14, 13, and 5–7 wt % of Ga) along with Ga hydroxides (oxyhydroxides?) were found for the first time in massive sulfide deposit in the Urals. The minerals identified within the cement of chalcopyrite–sphalerite breccias of the Shemur copper–zinc–massive sulfide deposit (Northern Urals) are associated with Ga-enriched sphalerite, chalcopyrite, and, less commonly, pyrite (33–364, 67–363, and 4–230 g/t, respectively).

Specific features of the geochemistry of manganiferous siliceous rocks confined to Devonian volcanogenic complexes of the Magnitogorsk belt in the South Urals are discussed. It is shown that with respect to the distribution of the major petrogenic and rare earth elements, as well as base and rare metals, manganese rocks are comparable with rocks of the low-temperature hydrothermal sources in active volcanic zones of the World Ocean. Our results agree well with the existing concepts about the hydrothermal-sedimentary origin of manganese deposits in the South Urals and corroborate this hypothesis with new independently obtained data.

New isotope and mineral data on manganese carbonates of the Mazul deposit (Krasnoyarsk region) in combination with morphology of ore bodies suggest that the ores were formed in several stages with the involvement of meteoric solutions through infiltration and, possibly, exfiltration mechanisms. Based on the geological–geochemical data, manganese carbonates of the Mazul deposit may be ascribed to a new genetic subtype of the catagenesis (epigenesis) zone.

The South Faizuly manganese deposit hosted in cherty rocks of the Magnitogorsk paleovolcanic belt has been studied. The geology, mineralogy, and chemistry of ores and host silicites (jasperites, jaspers, and cherty siltstones) are characterized. The deposit was formed in the following four consecutive stages: (1) sedimentation and diagenesis of ore-bearing sediments in the Middle Devonian, (2) metagenesis of Mn-bearing rocks in the Middle Devonian-Early Carboniferous, (3) hydrothermal-metasomatic stringer ore mineralization during tectonic deformation of volcanosedimentary rocks in the Middle Carboniferous-Permian, and (4) supergene alteration and partial denudation of the deposit in the Mesozoic-Quaternary. Models of Mn-bearing rock deposition in the proximal and distal zones of the hydrothermal solution discharge area are considered.