Left tusk’s fragments of the Pleistocene walrus were studied. Its fossil remains were found on the bank of the Pechora River in 2009. The analyses covered granulometric, chemical and normative-mineral composition of grounds inside the bones; thermal properties, chemical and microelemental composition of the tusk; X-ray diffraction parameters and chemical composition of bone bioapatite; macrostructure, elemental and amino acid composition of bone organic matter; isotopic composition of carbon, oxygen in bioapatite and carbon, nitrogen in bone collagen. Bioapatite was identified for moderately isotopically light carbon, characteristic of extracave fossil bones of the Pleistocene animals, and isotopically heavy oxygen, typical of seawater bicarbonate. The isotopic data for the organic matter of the Pechora walrus correlated with the similar characteristics of marine animals but simultaneously indicated not a mollusk diet, typical of modern walruses, but a fish diet. The latter fact evidenced the habitat and the diet of the Pechora walrus being untypical for marine predators.

-The methods of Infrared (IR) and Raman spectroscopy, as well as gas chromatography, were used to assess the distribution, content and composition of water-containing defects in variously deformed milky-white vein quartz of the Larino deposit. Weakly deformed quartz and quartz with intensive polygonization and recrystallization, in which water is present in molecular form, in fractures, channels, intergranular space, as well as in the composition of fluid inclusions, are analyzed. The content of water-containing defects, according to IR spectroscopy and gas chromatography, decreases in a series from weakly deformed primary granular coarse-grained quartz to blocked and recrystallized. The obtained results indicate the release of water during recrystallization, along the newly formed grain boundaries by diffusion and further homogenization to achieve an equilibrium state. Gas content also depends on the degree of deformation changes in samples and decreases from large coarse-grained differences to intensely deformed quartz with a high content of recrystallized grains.

Cholelithiasis (gallstone disease) is a multifactorial condition characterized by the formation of gallstones. Investigation of the composition of gallstones is essential for understanding the mechanisms of their formation and addressing various practical issues. Currently, it remains unclear which protein components are involved in gallstone formation and how they are related to other components of the stones. This study demonstrates a potential for the qualitative and quantitative determination of amino acids in gallstones of men and women of different ages using gas chromatography (GC-17A chromatograph, Shimadzu, Japan). The analysis of the amino acid composition of gallstones involves the acid hydrolysis of the samples in 6 M HCl at 105°C for 12 h, followed by purification, derivatization of the isolated amino acids, and their determination by gas chromatography. This method allows for the identification of both D- and L-forms of amino acids. A statistical analysis of the obtained data was performed using the STATISTICA 6.0. The study found that cholesterol gallstones in women under the age 50 have the lowest amino acid content. In the amino acid composition of cholesterol gallstones, glycine, along with the L-forms of serine, alanine, and glutamic acid, predominates. Cholesterol gallstones with a mineral component are typical in elderly women (over 60 years old) and middle-aged men (from 37 years old) and exhibit higher amino acid contents than pure cholesterol gallstones. In this type of stones, glycine and the L-forms of leucine, glutamic acid, and aspartic acid predominate. The highest amino acid content was found in pigment stones, both in men and women over the age 55. The amino acid composition of pigment-type stones is dominated by glycine and the L-forms of glutamic acid, aspartic acid, leucine, and alanine. D-amino acids were not detected in cholesterol gallstones. However, D-aspartic acid was found in cholesterol stones with a mineral component and in pigment gallstones. These findings suggest that gas chromatography is a suitable method for studying the amino acid composition of gallstones.

New remains of a Taymyr mammoth, including bones, bone collagen, hairs, skin, and soft (muscle and fat) tissues were studied comprehensively by mineralogical, spectroscopic, chromatographic, and isotope-geochemical methods. The results were used to infer the mammoth’s biological age and diet, paleoclimatic conditions, and the mechanisms and degree of fossilization of the remains.

The study of biominerals of a pathogenic nature in organisms is relevant and necessary for establishing the mechanism of their formation and solving many practical issues. Recently, intensive research has been carried out in the field of biochemistry of D-amino acids, it is believed that they can be potential biomarkers of various pathological processes in the human body. The presence of enantiomers of amino acids and their role in the mechanism of formation of gallstones, the issue has not yet been studied. The paper presents data on the distribution of D-enantiomers of amino acids, their content and ratio with L-forms in the composition of gallstones. A comparative analysis of the obtained results on gallstones with urinary stones is shown. It has been established that there is a relationship between the enantiomers of amino acids and the calcium mineral component.

Comprehensive mineralogical and geochemical studies of a representative sample of tephra from the Cumbre-Vyaha volcano (2020–2021 eruption), which has a gravel-psammitic granulometric composition and is characterized by an anomalously high degree of particle vesicularity, have been carried out. In terms of bulk chemical composition, this tephra corresponds to the transition from alkaline picrobasalts to alkaline basalts, differing fundamentally from the tephra ashes of marginal continental volcanoes. The studied tephra contains 45 trace elements with a total content of up to 2333 ppm, which exceeds that in the tephra of island-arc volcanoes. According to the ratio of geochemical criteria, tephra from Cumbre-Vyaha correspond to the average values for within-plate volcanoes in the oceans. The geochemical feature of the studied tephra is a strong enrichment in lanthanides, noble and platinoid metals. H2, CO, CO2, H2O, CH4, C2H4, C2H6, C3H6, C3H8 were found in the composition of the lithogenic gas phase separated by heating from the studied tephra. The proportions between inorganic components in the gas phase generally correspond to the boundary region between crustal and mantle-crustal derivatives, but a relatively low water content is found. Olivine of composition Fo73–84, essentially diopside clinopyroxene, andesine-bytovnite plagioclases, chrome spinels, phase-homogeneous solid solutions of ilmenite in magnetite, phases of Ni-Cu-bearing native iron, quartz, and sodium hydroxyl chlorides were identified and studied in microlites. In addition, dispersed carbon matter with carbon isotopic composition δ13СPDB = –30…–24‰ was found in the Cumbre-Vyaha tephra, which corresponds to the carbon isotope composition in abiogenic carbonaceous substances of volcanic origin. The totality of the results of mineralogical and geochemical studies characterizes the Cumbre-Vyaha volcano as a typical representative of within-plate oceanic plume volcanoes.

Lode gold deposits are widespread in orogenic belts of various ages and are a valuable gold source, but their genesis remains debatable. The close relationship between native gold and quartz was considered a reason to search for acid-magmatic sources of heat and fluids (i.e., granite intrusions), while small gabbro bodies were often ignored. Six minor gold deposits associated with NE-strike faults were studied in the Khudolaz area of the South Urals (Tukan, Bilyan-Tau, Fazly-Tau, Muildy-Tamak, Alasiya-II and Isyanbet-I). It was established, for the first time, that all of the studied deposits are similar geologically but differ in mineralogical diversity of ore-bearing quartz veins, which is due to the different composition of host rocks and ore-bearing intrusions of the Khudolaz (325–329 Ma, U-Pb) and the Ulugurtau (321 ± 15 Ma, Sm-Nd) ultramafic-mafic complexes. Results of the geochemical study of quartz veins (ICP MS) and their fluid inclusions (microthermometry, gas chromatography) showed that native gold was mostly precipitated at temperatures of 230–330 °C from a low- to moderate-saline (8–12 wt.% NaCl-eq.) H2O–CO2–CH4-bearing fluid, when weakly oxidized or near-neutral conditions, were replaced by reducing ones. No significant differences between barren milky white and ore-bearing brownish quartz veins were defined, which indicates their common formation settings and an impulse pattern of vein injection. The stable pattern of the fluid salinity, along with low hydrocarbon and N2 contents, as well as a narrow range of δ18O values, indicate a prevailing magmatogenic source with a certain influence of host rocks but without the influence of meteoric waters. Based on the presented data, the studied deposits were attributed to the epizonal orogenic type. This study shows the formation of lode gold deposits is possible without the participation of granite massifs.

Comprehensive mineralogical and geochemical studies were conducted in application to a representative sample of tephra from Cumbre Vieja Volcano (the 2020–2021 eruption). The tephra has a gravel-psammitic grain-size distribution, and is characterized by an anomalously high degree of particle vesicularity. The whole-rock composition of this tephra is consistent with the transition from alkaline picrobasalts to alkaline basalts, while being essentially different from the tephra ashes discharged by marginal continental volcanoes. The tephra was studied to detect 45 trace elements with whole-rock compositions occasionally reaching 2333 g/t, above the respective figure for the tephra of island arc volcanoes. Judging by the relationship among geochemical criteria, the Cumbre Vieja tephra is consistent with the average parameter values for intraplate volcanoes in oceans. One geochemical feature of this tephra consists in a strong enrichment in lanthanoids, as well as in noble and platinoid metals. The lithogenic gas phase which was obtained by heating the tephra sample was found to contain H 2 , CO, CO 2 , H 2 O, CH 4 , C 2 H 4 , C 2 H 6 , C 3 H 6 , and С 3 H 8 . The proportions among inorganic components in the gas phase as a whole correspond to the boundary region between crustal and mantle–crustal derivates, but water is in relatively low amounts. Microlites were found to contain Fo 73–84 olivine; this contains dominantly diopside clinopyroxene, andesine–bytownite plagioclase, chrome-spinellids, phase-homogeneous solid solutions of ilmenite in magnetite, phases of Ni-Cu bearing native iron, quartz, and sodic hydroxyl-chlorides. In addition, the Cumbre Vieja tephra was found to contain dispersed scattered carbonaceous material with δ 13 С PDB = –30…–24‰ as the isotopic composition of carbon, which is consistent with the isotopic composition of carbon in abiogenic carbonaceous materials of volcanogenic origin. The entire set of results of these mineralogical and geochemical studies characterizes Cumbre Vieja Volcano as a typical intraplate-oceanic plume volcano.

Mumijo is a product of natural origin, composed of a complex mixture of organic compounds and exhibiting physiological activity in some cases. The Altai mumijo is widely known in Russia, but Tuvinian mumijo has been studied much less. The data on the location of mumijo in the Republic of Tyva, its elemental composition, isotopic composition of carbon, amino acid spectrum, and mineral formations associated with mumijo are presented. The investigated mumijo is a waste product of small rodents, which underwent aqua transfer, weathering and bacterial processing.

Using a wide range of modern mineralogical and physicochemical methods, a representative collection of human bones from seven burial grounds of the Vychegda Permians of the 11th–14th centuries was studied. The microstructure of bones, their chemical and normative-mineral composition, the content of microelements, the nanoporosity of the organo-mineral composite, the composition and properties of bioanatite and bone collagen were analyzed. Fundamental differences in the properties of raw and so-called calcified bones are determined. Based on isotope data on bioapatite and collagen of raw bones, the climatic conditions for the existence of the Vychegda Permians and their diets were reconstructed.

Our multidisciplinary petrologic, mineralogical, and geochemical studies of volcanic material sampled from three chronologically discrete, but successive, ash discharges during the period from November 30, 2020 to January 18, 2021 were concerned with grain-size inhomogeneity, chemical and mineral phase composition, the concentrations of trace elements, the isotopy of Sr, Nd, and carbon, and with the composition of inorganic and organic lithogenic gases. For the first time volcanic ashes were found to contain eskolaite, mantle spinellids of the magnetite–magnesioferrite composition, hybrid compounds of Ca–Zn-carbonates with titanium formate, and polycomponent metallo-organic compounds. The net result was to obtain proof of a mantle–asthenosphere origin of the ash material and to identify a previously unknown pattern consisting in a conjugate temporal orderliness in the variations of many properties in the material sampled from the explosions. This seems to reflect the evolution of the melt in the mantle magma chamber.

This article provides the first description of the bacterial diversity in the Permian rock of the Upper Pechora salt basin. Halophilic and halotolerant bacteria of the classes Gammaproteobacteria (from the genera Halomonas , Marinobacter , and Idiomarina) and Actinomycetia (from the genus Dietzia) were isolated from the brines extracted during the underground dissolution of carnallite rocks in the pilot well of the Yakshinskoe deposit (Komi Republic, Russia) of potassium-magnesium salts. The analysis of 16S rRNA gene sequences cloned from the total DNA of the floatable part of the insoluble brine resi-dues revealed the following bacterial classes: Gammaproteobacteria (closely related to the genera Idio-marina , Marinimicrobium , Marinobacter , Methylophaga , and Pseudidiomarina), Betaproteobacteria (phenologically similar to the genera Achromobacter and Methylotenera), as well as Alphaproteobacteria and Flavobacteriia (related to the genera Sulfitobacter and Salegentibacter , respectively). Several identified phy-lotypes (clones 113YS, 8YS, 150YS, and 157YS) had a low level of similarity with the closest type strains of the genera Methylophaga (M. nitratireducenticrescens JAM1T , 96.86%), Salegentibacter (S. salarius ISL-6T , 98.58%), and Methylotenera (M. versatilis 301T , 98.05% and 98.19%). This indicates that the brine samples contained new, previously undescribed, bacterial taxa. The results obtained define and shape the future prospects for studying the phylogenetic and functional diversity of microorganisms in the salt strata of the Yakshinskoe deposit.

We studied 14 samples of gram-negative and gram-positive bacteria, unicellular yeasts and green algae using optical, atomic force and analytical scanning electron microscopy, thermal analysis, gas chromatography, infrared spectroscopy, inductively coupled plasma mass spectrometry and isotope mass spectrometry. In shape, the cells of microorganisms vary from rod-shaped to lenticular and coccoid, in size they range from mesonanometer to micrometer. A strong positive correlation was found between the extreme cell sizes. An admixture of inorganic chemical elements — Mg, Ca, Ba, Na, K, Cu, Zn, P, S, Cl and submicron-sized precipitates of mineral phases — carbonates, phosphate sulfates, hydrogen sulfate phosphates, hydrogen phosphates, halite, kaolinite, was found in the chemical composition of the studied microorganisms, metal alloys of brass composition, baddeleyite. Among the 45 microelements identified in microorganisms, there were 7 essential elements (E), 17 physiogenically active (FA) and 19 abiotic (AB). The total concentration of trace elements ranged from 0.003—0.26 wt. %. The value of the essential coefficient — E / AB — averaged 196 ± 153. Microorganisms were characterized by a mixed fat-protein elemental composition, they contained 14 amino acids belonging to the aliphatic, aromatic, basic, acidic, hydroxyl, imino and sulfur-containing groups. The total amino acid content ranged from 409 to 942 (682 ± 221) mg/g. Up to half of the amino acids were represented by the left (L) and right (D) enantiomers. The degree of racemization (D / L) ranged from 0.01 to 0.37. Yeast and chlorella were characterized by the most isotopically heavy composition of carbon in combination with relatively isotopically light nitrogen. In bacteria, a statistically lighter carbon was found in combination with a much heavier nitrogen. According to a number of properties — the chemical composition of organic matter, microelements, the degree of enrichment with antibiotic elements, the content of amino acids and the degree of their racemization — gram-negative and gram-positive bacteria differed. In general, the studied biological microorganisms were fundamentally different from the abiogenic organic substances found in meteorites and products of modern volcanism regarding their elemental and amino acid composition, carbon and nitrogen isotopes.

This paper reports the first multidisciplinary petrologic, mineralogical, and geochemical studies of the near-crater tephra discharged by the 1669 catastrophic eruption of Etna stratovolcano, Sicily. We studied the grain-size distribution, chemical and mineral-phase composition of the tephra. We determined the composition of trace elements and the composition of encapsulated lithogenic gases. Etna is classified as an intraplate volcano with a deep-seated magma chamber. Of special importance is the fact that the Etnean products were found to contain volcanogenic organoids that have phase, elemental, and isotope compositions similar to the organoids encountered in diamond-bearing products discharged by some Kamchatka volcanoes. This corroborates out earlier inference that carbonaceous abiogenesis is ubiquitous in the conditions of onshore volcanism.

The composition and distribution of alkylbenzenes, alkyltoluenes, and 2-methyl-2-(4,8,12-trimethyltridecyl)chromans (MTTC) in the aromatic hydrocarbon fraction isolated from the Lower Permian silty-clayey and salt rocks of the Upper Pechora potassium–magnesium salt basin (Yakshinskoe deposit) are presented. The studies have shown the wide distribution of alkylbenzenes and alkyltoluenes under hypersaline environment (stages of the halite and sylvite precipitation) at low organic matter maturity. The revealed differences in n-alkylbenzenes and n-alkyltoluene distributions are associated with the predominance of various biological precursors (halophilic archaea, prasinophytes, planktonic algae, etc.) during the salt deposition of the Upper Pechora Basin. Our data confirmed the predominance of hexadecylbenzene (C22) among n-alkylbenzenzenes under hypersaline environments. The presence of phytanylbenzene and phytanyltoluene was established in the rocks of the Upper Pechora salt basin. It was found that the maximum content of phytanylbenzene is correlated with elevated contents of phytane and hexadecylbenzene, which suggests their common source and allows us to consider these compounds as indicators of paleohypersalinity. The abundance of 5,7,8-trimethyl-MTTC at low concentrations of mono- and dimethyl-MTTC indicates significant input of fresh water into the evaporite basin during the deposition of the underlying rock salt horizon.

This paper presents the results of a quantitative analysis of impurity elements present in the structural form and composition of mineral and fluid inclusions in the quartz of the Kuznechikhinskoe deposit. The studies have been carried out using ICP–OES and FT–IR spectroscopy, electron paramagnetic resonance (EPR), and gas chromatography. It has been shown that the concentrations of mineral and fluid inclusions are low due to the deposit formation conditions, which positively affects the purity of quartz concentrates obtained. The main impurity is Al, present in the composition of mineral and fluid inclusions and in the crystal lattice of quartz itself. Spectroscopic studies allowed localizing impurities in the quartz and selecting an effective staged concentration process. The quartz samples are first crushed to the fraction of 0.1 to 0.4 mm, then subjected to electromagnetic separation, agglomeration treatment, and microwave decrepitation, and, at the final stage, undergo acid treatment in a combination of hydrofluoric and hydrochloric acids. The finishing deionized water washing and drying complete the deep concentration process to produce high-purity concentrates.

The purpose of work is to determine the ratio of amino acid enantimers in bioapatite of human teeth and the influence of pathological processes in periodontium on the degree of racemization of amino acids. Objects of research - enamel without signs of caries, root dentin of permanent teeth and enamel of human carious milk teeth (n=16). Identification and determination of amino acid content in the samples was performed on a GC-17A gas chromatograph (Shimadzu, Chirasil-L-Val capillary column). D-forms were detected for three amino acids: alanine (Ala), aspartic (Asp) and glutamic (Glu) acids. Studies have shown the highest D/L Asp and Glu ratios for bioapatite enamel of tooth, removed due to pathological changes in periodontal tissues, and root dentin of the retained teeth. The ratio D/L Asp indicates the absence of relationship between the degree of racemization of aspartic acid in the teeth involved in pathological processes and biological age. Low D/L ratios of Asp, Glu and Ala are determined in teeth removed by orthodontic indications. It was noted that the use of racemization degree of aspartic acid in enamel and dentin bioapatite as one of the methods for assessing the exact biological age of unidentified remains is problematic without identifying inflammatory and degenerative processes in periodontal tissue.