The present work contributes to the essential questions on calcium oxalate formation under the influence of lithobiont community organisms. We have discovered calcium oxalates in lichen thalli on surfaces of apatite-nepheline rocks of southeastern and southwestern titanite-apatite ore fields of the Khibiny peralkaline massif (Kola Peninsula, NW Russia) for the first time; investigated biofilm calcium oxalates with different methods (X-ray powder diffraction, scanning electron microscopy, and EDX analysis) and discussed morphogenetic patterns of its formation using results of model experiments. The influence of inorganic and organic components of the crystallization medium on the phase composition and morphology of oxalates has been analyzed. It was shown that, among the complex of factors controlling the patterns of biogenic oxalate formation, one of the main roles belongs to the metabolic activity of the lithobiont community organisms, which differs significantly from the activity of its individuals.

The Lovozero Alkaline Massif intruded through the Archaean granite-gneiss and Devonian volcaniclastic rocks about 360 million years ago, and formed a large (20 × 30 km) laccolith-type body, rhythmically layered in its lower part (the Layered Complex) and indistinctly layered and enriched in eudialyte-group minerals in its upper part (the Eudialyte Complex). The Eudialyte Complex is composed of two groups of rocks. Among the hypersolvus meso-melanocratic alkaline rocks (mainly malignite, as well as shonkinite, melteigite, and ijolite enriched with the eudialyte-group minerals, EGM), there are lenses of subsolvus leucocratic rocks (foyaite, fine-grained nepheline syenite, urtite with phosphorus mineralization, and primary lovozerite-group minerals). Leucocratic rocks were formed in the process of the fractional crystallization of melanocratic melt enriched in Fe, high field strength elements (HFSE), and halogens. The fractionation of the melanocratic melt proceeded in the direction of an enrichment in nepheline and a decrease in the aegirine content. A similar fractionation path occurs in the Na₂O-Al₂O₃-Fe₂O₃-SiO₂ system, where the melt of the “ijolite” type (approximately 50% of aegirine) evolves towards “phonolitic eutectic” (approximately 10% of aegirine). The temperature of the crystallization of subsolvus leucocratic rocks was about 550 °C. Hypersolvus meso-melanocratic rocks were formed at temperatures of 700–350 °C, with a gradual transition from an almost anhydrous HFSE-Fe-Cl/F-rich alkaline melt to a Na(Cl, F)-rich water solution. Devonian volcaniclastic rocks underwent metasomatic treatment of varying intensity and survived in the Eudialyte Complex, some remaining unchanged and some turning into nepheline syenites. In these rocks, there are signs of a gradual increase in the intensity of alkaline metasomatism, including a wide variety of zirconium phases. The relatively high fugacity of fluorine favored an early formation of zircon in apo-basalt metasomatites. The ensuing crystallization of aegirine in the metasomatites led to an increase in alkali content relative to silicon and parakeldyshite formation. After that, EGM was formed, under the influence of Ca-rich solutions produced by basalt fenitization.

The Kovdor phoscorite-carbonatite ore-pipe rocks form a natural series, where apatite and magnetite first gradually increase due to the presence of earlier crystallizing forsterite in the pipe marginal zone and then decrease as a result of carbonate development in the axial zone. In all lithologies, magnetite grains contain (oxy)exsolution inclusions of comparatively earlier ilmenite group minerals and/or later spinel, and their relationship reflects the concentric zonation of the pipe. The temperature and oxygen fugacity of titanomagnetite oxy-exsolution decreases in the natural rock sequence from about 500 °C to about 300 °C and from NNO + 1 to NNO − 3 (NNO is Ni-NiO oxygen fugacity buffer), with a secondary positive maximum for vein calcite carbonatite. Exsolution spinel forms spherical grains, octahedral crystals, six-beam and eight-beam skeletal crystals co-oriented with host magnetite. The ilmenite group minerals occur as lamellae oriented along {111} and {100} planes of oxy-exsolved magnetite. The kinetics of inclusion growth depends mainly on the diffusivity of cations in magnetite: their comparatively low diffusivities in phoscorite and carbonatites of the ore-pipe internal part cause size-independent growth of exsolution inclusions; while higher diffusivities of cations in surrounding rocks, marginal forsterite-rich phoscorite and vein calcite carbonatite result in size-dependent growth of inclusions.

This paper reviews the available information on the beryllium mineralogy of the different type of occurrences in the Kola Peninsula, northwest Russia. Beryllium mineralization in the region is mainly associated with alkaline and felsic rocks, which differ significantly in petrological, geochemical, mineralogical features and age. In total 28 beryllium minerals are established on the Kola Peninsula up today. Beryl is one of the ore minerals in the differentiated granite pegmatites of the Kolmozerskoe lithium deposit. A large diversity of beryllium minerals occur in the pegmatites and hydrothermal veins formed in the late stages of the Lovozero and Khibiny alkaline massifs. Most of these minerals, as leifite, lovdarite, odintsovite, sphaerobertrandite and tugtupite are rare in other environments and have unique properties. These minerals formed under conditions of extreme alkalinity and their formation was favored by abrupt changes in the alkalinity regimes. Some of minerals, as chrysoberyl in xenoliths of hornfels, genthelvite and unique intergrowth of meliphanite and leucophanite formed in contrasting geochemical fronts between felsic/intermediate and mafic rocks.

The pyrochlore supergroup minerals (PSM) are typical secondary phases that replace (with zirconolite–laachite) earlier Sc-Nb-rich baddeleyite under the influence of F-bearing hydrothermal solutions, and form individual well-shaped crystals in surrounding carbonatites. Like primary Sc-Nb-rich baddeleyite, the PSM are concentrated in the axial carbonate-rich zone of the phoscorite-carbonatite complex, so their content, grain size and chemical diversity increase from the pipe margins to axis. There are 12 members of the PSM in the phoscorite-carbonatite complex. Fluorine- and oxygen-dominant phases are spread in host silicate rocks and marginal carbonate-poor phoscorite, while hydroxide-dominant PSM occur mainly in the axial carbonate-rich zone of the ore-pipe. Ti-rich PSM (up to oxycalciobetafite) occur in host silicate rocks and calcite carbonatite veins, and Ta-rich phases (up to microlites) are spread in intermediate and axial magnetite-rich phoscorite. In marginal (apatite)-forsterite phoscorite, there are only Ca-dominant PSM, and the rest of the rocks include Ca-, Na- and vacancy-dominant phases. The crystal structures of oxycalciopyrochlore and hydroxynatropyrochlore were refined in the $Fd\overline{3}m$ space group with R₁ values of 0.032 and 0.054 respectively. The total difference in scattering parameters of B sites are in agreement with substitution scheme ^BTi⁴⁺ + ^YOH^‒ = ^BNb⁵⁺ + ^YO^2‒. The perspective process flow diagram for rare-metal “anomalous ore” processing includes sulfur-acidic cleaning of baddeleyite concentrate from PSM and zirconolite–laachite impurities followed by deep metal recovery from baddeleyite concentrate and Nb-Ta-Zr-U-Th-rich sulfatic product from its cleaning.