pdf № 374, February

DOI: 10.19110/geov.2026.2.1

The simultaneous presence of two minerals of the ilmenite group has been established in the granites of the third phase of the Turochak complex intrusion (γD₁t). They differ in size, location in the rock and chemical composition. Magnetite grains occur together with them. Manganoilmenite (MnO 17.95—22.68 wt.%) occurs as euhedral grains 150—200 µm in size, confined to biotite laths. The iron-manganese ratio varies from 1.18 to 1.63. The pyrophanite minal makes up 38—45%, hematite minal is rarely present (up to 2%). The general formula is as follows: (Fe²⁺_0.53—0.60Mn_0.38—0.45Fe³⁺_0—0.02)_S1.00—1.01Ti_0.99—1.00O₃. Pyrophanite (MnO 24.35—27.18 wt.%) is represented by small (up to 50 µm) euhedral grains located in the intergranular space. The iron-manganese ratio is less than unity (FeO/MnO from 0.74 to 0.93). The pyrophanite end-member makes up from 52 to 58%, the hematite end-member is absent. The generalized formula is (Mn_0.52—0.58Fe²⁺_0.42—0.48)_S1.00Ti_1.00O₃. Magnetite in the rock occurs as isometric euhedral grains, mainly confined to biotite, no more than 40 µm in size. Single grains are found in plagioclase; their size reaches 150—180 µm. Magnetite is characterized by the constant presence of titanium (TiO₂ 5.87—7.30 wt.%) and manganese (up to 0.20%), the amount of total iron is FeO 92.59—94.02 wt.%. The general formula of magnetite is Fe²⁺_1.16—1.20(Fe³⁺_1.60—1.68Ti_0.16—0.20)_S1.80—1.84O₄. The oxygen activity calculated for the "magnetite-manganoilmenite pair is from –26 to –24, and for the magnetite-pyrophanite pair –36 to –32, which indicates reducing conditions during their crystallization.

Keywords: granite, manganoilmenite, pyrophanite, magnetite, Turochak complex, Altai Mountains

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DOI: 10.19110/geov.2026.2.2

Tungsten is a scarce mineral raw material essential for critical industries. The country is in acute need of developing new tungsten deposits. The Shauyrkhyg prospective area is currently a site that requires detailed study. Investigating the composition and structure of the ore using a set of technological mineralogy methods (optical-mineralogical, X-ray diffraction, chemical, and electron microscopy analysis) allows determining its processing prospects.

Keywords: scheelite ore, scheelite, tungstite, mineralogical features

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DOI: 10.19110/geov.2026.2.3

We present a study of a reference collection of urinary stone samples from men and women aged 27—83 years, as well as urine from patients with urolithiasis and chronic pyelonephritis, using a wide range of modern experimental research methods. The chemical and phase composition, trace element content, amino acid composition and content in proteins, and the isotopic composition of carbon and nitrogen are analyzed. Biominerals are found in the urinary stones, covering virtually the entire modern range of mineral types: elementary substances (metals), chalcogenides (sulfides), halides (chlorides), oxides (magnetite, SiO₂ phase), silicates (aluminosilicates), and oxygen salts. In addition to minerals, the stones also contain so-called mineraloids, represented by hydrous calcium oxalates and uric acid. Fifteen protein amino acids, including seven essential ones, are identified in the studied samples. Three amino acids contain a small amount of the D-enantiomer. The isotopic composition of carbon and nitrogen in organic matter found in human stones and urine is unique and differs from that found in human bones, the Earth's atmosphere, and sedimentary rocks. However, urinary stones share a carbon isotopic composition similar to organic polymers formed by modern volcanism.

Keywords: urinary stones, mineral formation in the human body, biominerals

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DOI: 10.19110/geov.2026.2.4

In recent years, soil pollution with potentially toxic elements has become an important issue causing widespread concern because it is a significant factor threatening the environment. The mining industry is one of the main sources of negative impact. Moreover, the soil is the main geochemical absorber of various pollutants. In the present study, using ecological-geochemical and toxicological pollution indices, such as the Nemerov index (INI), pollution load index (PLI), total pollution index (Z_c), potential ecological risk index (RI), the levels of chemical pollution of soils of the industrial site of the Aikhal Mining and Processing Division with potentially toxic elements (Pb, Ni, Mn, Cd, Co, Cr, Zn, Cu, As) are identified. As a result of calculations of these indices, the elements that make the main contribution to the pollution of the studied soils are identified. The pollutant elements for INI are As, Ni and Cu; for PLI — As, Ni, Cu, Zn, Cr, Co, Mn; for Zc — As, Ni, Cu, Zn, Cr; for RI — Ni. Nickel is the main environmental risk factor for soils at the Aikhal Mining and Processing Division's industrial site. Using spatial distribution maps, localized areas with high geoecological stress are identified near the processing plants.

Keywords: potentially toxic elements, soil pollution, pollution indices, geoecological risk, Daldyn-Alakit diamond-bearing region, Alakit-Markhinsky kimberlite field

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