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The aim of this research was to study the rare earth (REE) minerals in ooidal ironstone deposits of the West Siberian basin and the Turgai depression. Authigenic minerals (monazite and cerite) were described, and their main mineral form was identified as light rare earth element phosphate (LREE-phosphate) in this study. LREE-phosphate is included in ferruginous ooids, peloids, and oncoids and forms a consistent mineral association with Fe-hydroxides (goethite and its hydrated amorphous derivatives) and Fe-rich layered silicates (Fe-illite-smectite, chamosite, berthierine). The constancy of the mineral association in two deposits of different ages indicates a general mechanism behind the formation of these minerals. LREE-phosphates (authigenic monazite) are characterized by microscopic sizes (up to 24 μm), diverse morphology (mainly spherical or xenomorphic), and occupy spaces between the micro-cortex in ferruginous spheroids. This mineral can be found in other deposits of ooidal ironstone. According to its mineralogical and chemical characteristics, LREE-phosphate mainly belongs to the authigenic (nodular or “gray”) monazite. However, the incomplete (not 100%) correspondence of Kikuchi bands with the reference monazite does not allow its reliable identification. Based on its small size, chemical leaching or bacterial interaction is recommended to extract REE from ooidal ironstone while predicting the associated removal of phosphorus from iron ore due to its dominant phosphate mineral form. Ooidal ironstone should be considered a complex deposit and an unconventional natural type of REE ores as an example of the largest Bakchar and Lisakovsk deposits.

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Applying scanning electron microscope (SEM), energydispersive microanalyzer and X-ray fluorescence microscope the ore mineral composition in Central gold-ore field (Kuznetsk Alatau) was investigated. Eleven new minerals were detected in this ore field. The differentiated behavior of mineral formation stages in veins and nearveined beresites was determined. The composition of native gold was studied, as well as the distribution of trace elements in pyrite.

Glauconite-containing rocks found within the boundaries of the Bakchar deposit include the following: glauconite ores (glauconitolite), glauconite sandstone, hydrogoethite-chlorite, iron ores with glauconite. Glauconite content in glauconite ores is 50…70 %, in glauconite sandstone -20…40 %, in hydrogoethite-chlorite ores-10…20 %. This paper describes the technological characteristics of glauconite rocks. The authors proposed the optimal technological scheme of producing glauconite concentrate. It has been defined that the most highly-qualified product with commercial components 90…100 % is recovered from glauconite ores. It has been evaluated that Bakchar glauconite is applicable as a favorable mineral fertilizer based on the concentrate produced from enriched hydrogoethite-chlorite ores. Experimentally, it has been proved that this concentrate has a positive effect on the growth of oats (Avéna satíva). This is a direct indicator of its practical applicability. Obtained results indicate the fact that the extraction and application of Bakchar glauconite could be widely used in agriculture.