Pub Date : 2024-02-07DOI: 10.1134/s1075701523070024
M. S. Avdontceva, S. V. Krivovichev, M. G. Krzhizhanovskaya, V. N. Bocharov, N. S. Vlasenko, D. V. Spiridonova
Abstract
The crystal chemical peculiarities of cacoxenite from the Těškov quarry (Bohemia, Czech Republic) are studied using single crystal X-ray analysis and thermal X-ray analysis, electron-microprobe analysis, and infrared (IR) and Raman spectroscopy. The crystal structure of cacoxenite (hexagonal system, sp. gr. P63/m, a = 27.5677(4) Å, c = 10.5364(3) Å, V = 6934.64(16) Å3) is refined to R1 = 0.052 by 4637 independent reflections. The crystal structure is based on two independent structural blocks, which form an open-framework (the minimum free pore diameter is 15.1 Å). The crystal structure of cacoxenite is stable up to 190°C. The empirical formula of the mineral (based on 17 P atoms) is (({text{Fe}}_{{19.98}}^{{3 + }})Al4.97)Σ24.95O6(PO4)17(OH8.52Cl3.48)Σ12(H2O)24⋅ nH2O (n ∼ 50). The most intense bands of IR and Raman spectra in a range from 400 to 1200 cm–1 correspond to stretching and bending vibration modes of the phosphate groups. The presence of water in the structure is confirmed by the presence of an intense band in the IR spectrum in the area of 1624 cm–1 (O–H vibrations), as well as the absorption band with maximum of 3357 cm–1, which corresponds to stretching vibrations of the Fe(Al)–OH bond and H2O molecules. The calculation of structural complexity of cacoxenite for the framework without H-corrections and with the addition of framework-related H-positions shows a very complex structure of the mineral (2312.464 bit/cell).
摘要 利用单晶 X 射线分析和热 X 射线分析、电子探针分析、红外光谱和拉曼光谱，研究了 Těškov 采石场（捷克共和国波希米亚）出产的埃克森石的晶体化学特性。通过 4637 次独立反射，将可可碱石（六方体系，sp. gr. P63/m，a = 27.5677(4) Å，c = 10.5364(3) Å，V = 6934.64(16) Å3）的晶体结构细化为 R1 = 0.052。该晶体结构基于两个独立的结构块，它们形成了一个开放框架（最小自由孔径为 15.1 Å）。可可碱石的晶体结构在 190°C 以下都很稳定。该矿物的经验公式（基于 17 个 P 原子）为 (({{Fe}}_{{19.98}}^{{3 + }})Al4.97)Σ24.95O6(PO4)17(OH8.52Cl3.48)Σ12(H2O)24⋅ nH2O (n ∼ 50)。红外光谱和拉曼光谱中 400 至 1200 cm-1 范围内最强烈的波段对应于磷酸基团的伸展和弯曲振动模式。在红外光谱中，1624 cm-1（O-H 振动）区域存在一条强波段，以及最大值为 3357 cm-1 的吸收波段（对应于 Fe(Al)-OH 键和 H2O 分子的伸缩振动）证实了结构中水的存在。在不进行 H 校正和添加与框架相关的 H 位置的情况下，对卡考氙石框架结构复杂性的计算显示，该矿物的结构非常复杂（2312.464 位/单元）。
{"title":"Cacoxenite—a Complex Phosphate with a Modular Structure","authors":"M. S. Avdontceva, S. V. Krivovichev, M. G. Krzhizhanovskaya, V. N. Bocharov, N. S. Vlasenko, D. V. Spiridonova","doi":"10.1134/s1075701523070024","DOIUrl":"https://doi.org/10.1134/s1075701523070024","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The crystal chemical peculiarities of cacoxenite from the Těškov quarry (Bohemia, Czech Republic) are studied using single crystal X-ray analysis and thermal X-ray analysis, electron-microprobe analysis, and infrared (IR) and Raman spectroscopy. The crystal structure of cacoxenite (hexagonal system, sp. gr. <i>P</i>6<sub>3</sub>/<i>m</i>, <i>a</i> = 27.5677(4) Å, <i>c</i> = 10.5364(3) Å, <i>V</i> = 6934.64(16) Å<sup>3</sup>) is refined to <i>R</i><sub>1</sub> = 0.052 by 4637 independent reflections. The crystal structure is based on two independent structural blocks, which form an open-framework (the minimum free pore diameter is 15.1 Å). The crystal structure of cacoxenite is stable up to 190°C. The empirical formula of the mineral (based on 17 P atoms) is (<span>({text{Fe}}_{{19.98}}^{{3 + }})</span>Al<sub>4.97</sub>)<sub>Σ24.95</sub>O<sub>6</sub>(PO<sub>4</sub>)<sub>17</sub>(OH<sub>8.52</sub>Cl<sub>3.48</sub>)<sub>Σ12</sub>(H<sub>2</sub>O)<sub>24</sub>⋅ <i>n</i>H<sub>2</sub>O (<i>n</i> ∼ 50). The most intense bands of IR and Raman spectra in a range from 400 to 1200 cm<sup>–1</sup> correspond to stretching and bending vibration modes of the phosphate groups. The presence of water in the structure is confirmed by the presence of an intense band in the IR spectrum in the area of 1624 cm<sup>–1</sup> (O–H vibrations), as well as the absorption band with maximum of 3357 cm<sup>–1</sup>, which corresponds to stretching vibrations of the Fe(Al)–OH bond and H<sub>2</sub>O molecules. The calculation of structural complexity of cacoxenite for the framework without H-corrections and with the addition of framework-related H-positions shows a very complex structure of the mineral (2312.464 bit/cell).</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"100 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139763053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-07DOI: 10.1134/s1075701523070127
S. S. Ugap’eva, A. E. Molotkov, S. A. Gromilov, V. P. Afanasiev, A. D. Pavlushin, A. P. Eliseev, V. I. Popov
Abstract
This paper reports new study data on structural features of polycrystalline diamonds (yakutites) from placers of the Anabar diamondiferous region obtained by X-ray and optical spectroscopy. All studied samples are fine-grained (up to 1 μm) polycrystals. The diffractograms of most samples show reflexes related to lonsdaleite defects in the diamond structure. Yakutites are inhomogeneous: diffractograms of different parts of diamond aggregates show different reflections of texture and micrograins with a monocrystalline structure. A “bell” in the single-phonon region of IR spectra indicates defects in the crystal structure of yakutites and a significant structural stress. An aggregated nitrogen line is absent in the photoluminescence spectra of yakutites, likely due to the fact that they were ejected outside the crater after the solid-phase synthesis stage and were relatively rapidly cooled down.
摘要 本文报告了通过 X 射线和光学光谱法获得的关于阿纳巴尔金刚石产区块矿中多晶金刚石 （雅库特岩）结构特征的新研究数据。研究的所有样品都是细粒度（最多 1 μm）多晶体。大多数样品的衍射图都显示出与金刚石结构中龙氏石缺陷有关的反射。雅库特岩是不均匀的：金刚石集合体不同部分的衍射图显示出不同的纹理反射和单晶结构的微晶粒。红外光谱单声子区域的 "钟声 "表明雅库特岩的晶体结构存在缺陷，结构应力很大。白云石的光致发光光谱中没有聚集氮线，这可能是由于白云石在固相合成阶段之后被喷射到陨石坑外，并相对迅速地冷却下来。
{"title":"Texture and Structure Features of Yakutites from Placers of the Anabar Diamondiferous Region","authors":"S. S. Ugap’eva, A. E. Molotkov, S. A. Gromilov, V. P. Afanasiev, A. D. Pavlushin, A. P. Eliseev, V. I. Popov","doi":"10.1134/s1075701523070127","DOIUrl":"https://doi.org/10.1134/s1075701523070127","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>This paper reports new study data on structural features of polycrystalline diamonds (yakutites) from placers of the Anabar diamondiferous region obtained by X-ray and optical spectroscopy. All studied samples are fine-grained (up to 1 μm) polycrystals. The diffractograms of most samples show reflexes related to lonsdaleite defects in the diamond structure. Yakutites are inhomogeneous: diffractograms of different parts of diamond aggregates show different reflections of texture and micrograins with a monocrystalline structure. A “bell” in the single-phonon region of IR spectra indicates defects in the crystal structure of yakutites and a significant structural stress. An aggregated nitrogen line is absent in the photoluminescence spectra of yakutites, likely due to the fact that they were ejected outside the crater after the solid-phase synthesis stage and were relatively rapidly cooled down.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"77 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139755674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-07DOI: 10.1134/s1075701523070048
Yu. L. Gulbin, I. A. Abdrakhmanov, I. M. Gembitskaya, E. A. Vasiliev
Abstract
The Bunger Hills, East Antarctica occupies an area of about 300 km2 and is underlain by large Neoarchean tonalite–granite orthogneiss bodies in the southern part and a Paleoproterozoic volcanosedimentary sequence, buckled into isoclinal folds and metamorphosed to the granulite facies, in the northern. The sequence is intruded by large syncollisional charnockite plutons and consists predominantly of strongly migmatized garnet–sillimanite–cordierite paragneisses (metapelitic granulites). A characteristic feature of the mineral composition of these rocks is the paragenesis of Zn-poor spinel and quartz. The P–T conditions for the equilibrium of these two minerals are 6–7 kbar and 970–1030°C as estimated with the method of isochemical phase diagrams and 985–1005°C, as calculated with the aid of Ti-in-quartz thermobarometry (Huang and Audétat, 2012). Quartz contains needle-shaped microinclusions less than 1 μm in thickness aligned along the [0001] direction and evenly distributed throughout the quartz grains. According to data of electron-probe analysis, they are heterogeneous and consist of rutile and spinel (hercynite) intergrowths. The available data suggest that the genesis of the microinclusions is related to the exsolution process and the diffusion of structural impurities in quartz (Al, Fe, and Ti) in the direction of parallel translation-slip zones (10(bar {1})10), along which the high-temperature plastic deformations of quartz took place during the postpeak stage. The appearance of spinel in the microparagenesis of the oxides of the Al–Fe–Mg–Ti system is interpreted as a result of the processes synchronous with the intracrystal diffusion: the open-system diffusion of Mg atoms along the weakness zones of the quartz lattice or the infiltration of Mg-rich fluids along the microscopic cleavage planes formed as a result of hydrofracturing.
{"title":"Oriented Microinclusions of Al–Fe–Mg–Ti Oxides in Quartz from Metapelitic Granulites of the Bunger Hills, East Antarctica","authors":"Yu. L. Gulbin, I. A. Abdrakhmanov, I. M. Gembitskaya, E. A. Vasiliev","doi":"10.1134/s1075701523070048","DOIUrl":"https://doi.org/10.1134/s1075701523070048","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The Bunger Hills, East Antarctica occupies an area of about 300 km<sup>2</sup> and is underlain by large Neoarchean tonalite–granite orthogneiss bodies in the southern part and a Paleoproterozoic volcanosedimentary sequence, buckled into isoclinal folds and metamorphosed to the granulite facies, in the northern. The sequence is intruded by large syncollisional charnockite plutons and consists predominantly of strongly migmatized garnet–sillimanite–cordierite paragneisses (metapelitic granulites). A characteristic feature of the mineral composition of these rocks is the paragenesis of Zn-poor spinel and quartz. The <i>P–T</i> conditions for the equilibrium of these two minerals are 6–7 kbar and 970–1030°C as estimated with the method of isochemical phase diagrams and 985–1005°C, as calculated with the aid of Ti-in-quartz thermobarometry (Huang and Audétat, 2012). Quartz contains needle-shaped microinclusions less than 1 μm in thickness aligned along the [0001] direction and evenly distributed throughout the quartz grains. According to data of electron-probe analysis, they are heterogeneous and consist of rutile and spinel (hercynite) intergrowths. The available data suggest that the genesis of the microinclusions is related to the exsolution process and the diffusion of structural impurities in quartz (Al, Fe, and Ti) in the direction of parallel translation-slip zones (10<span>(bar {1})</span>10), along which the high-temperature plastic deformations of quartz took place during the postpeak stage. The appearance of spinel in the microparagenesis of the oxides of the Al–Fe–Mg–Ti system is interpreted as a result of the processes synchronous with the intracrystal diffusion: the open-system diffusion of Mg atoms along the weakness zones of the quartz lattice or the infiltration of Mg-rich fluids along the microscopic cleavage planes formed as a result of hydrofracturing.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"7 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139755664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-07DOI: 10.1134/s1075701523070140
E. A. Vasilev, A. A. Kudriavtsev, I. V. Klepikov, A. V. Antonov
Abstract
Diamond crystals of various morphological types, including carbonado, were studied by the electron backscatter diffraction method. Cases of inhomogeneities of different natures were revealed: interpenetrant and mechanical twins, incoherent intergrowth, and splitting growth. Differences in the distribution pattern of boundary angles for different types of inhomogeneities have been shown: predominantly discrete in intergrowths, continuous distribution of low-angle boundaries in ballas diamonds, and continuous random distribution in carbonado. It has been shown that Rose channels in diamond arise as a result of etching at the intersection of mechanical twins. The revealed mechanical twins have a thickness of 60–600 nm.
{"title":"Diversity of the Structure of Diamond Crystals and Aggregates: Electron Backscatter Diffraction Data","authors":"E. A. Vasilev, A. A. Kudriavtsev, I. V. Klepikov, A. V. Antonov","doi":"10.1134/s1075701523070140","DOIUrl":"https://doi.org/10.1134/s1075701523070140","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Diamond crystals of various morphological types, including carbonado, were studied by the electron backscatter diffraction method. Cases of inhomogeneities of different natures were revealed: interpenetrant and mechanical twins, incoherent intergrowth, and splitting growth. Differences in the distribution pattern of boundary angles for different types of inhomogeneities have been shown: predominantly discrete in intergrowths, continuous distribution of low-angle boundaries in ballas diamonds, and continuous random distribution in carbonado. It has been shown that Rose channels in diamond arise as a result of etching at the intersection of mechanical twins. The revealed mechanical twins have a thickness of 60–600 nm.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"37 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139763060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-07DOI: 10.1134/s1075701523070139
K. L. Ushakova, M. V. Charykova, V. G. Krivovichev, N. M. Efimenko, N. V. Platonova, V. N. Bocharov, A. S. Mazur
Abstract
The purpose of this work was to synthesize hexahydrate aluminum selenite Al2(SeO3)3⋅6H2O (analogous to the mineral alfredopetrovite) and study its solubility in water. Al2(SeO3)3⋅6H2O is synthesized from AlCl3 and Na2SeO3 solutions at room temperature and atmospheric pressure. The obtained samples were studied using powder diffractometry, infrared and Raman spectroscopy, energy-dispersive X-ray microanalysis, nuclear magnetic resonance spectroscopy, and complex thermal analysis. Solubility was determined by isothermal saturation in ampoules at 25°C. Solubility products were calculated using Geochemist’s Workbench software package (GMB 9.0, SpecE8 program). As a result of the calculation, the average value logKsp[Al2(SeO3)3⋅6H2O] = –28.3 ± 0.5 was obtained. An Eh–pH diagram is constructed for the Al–Se–H2O system, which was used to analyze the stability of alfredopetrovite in near-surface conditions.
{"title":"Thermodynamics of Arsenates, Selenites, and Sulfates in the Oxidation Zone of Sulfide Ores. XV. Synthetic Analog of Alfredopetrovite: Composition, Properties, and Stability Limits","authors":"K. L. Ushakova, M. V. Charykova, V. G. Krivovichev, N. M. Efimenko, N. V. Platonova, V. N. Bocharov, A. S. Mazur","doi":"10.1134/s1075701523070139","DOIUrl":"https://doi.org/10.1134/s1075701523070139","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The purpose of this work was to synthesize hexahydrate aluminum selenite Al<sub>2</sub>(SeO<sub>3</sub>)<sub>3</sub>⋅6H<sub>2</sub>O (analogous to the mineral alfredopetrovite) and study its solubility in water. Al<sub>2</sub>(SeO<sub>3</sub>)<sub>3</sub>⋅6H<sub>2</sub>O is synthesized from AlCl<sub>3</sub> and Na<sub>2</sub>SeO<sub>3</sub> solutions at room temperature and atmospheric pressure. The obtained samples were studied using powder diffractometry, infrared and Raman spectroscopy, energy-dispersive X-ray microanalysis, nuclear magnetic resonance spectroscopy, and complex thermal analysis. Solubility was determined by isothermal saturation in ampoules at 25°C. Solubility products were calculated using Geochemist’s Workbench software package (GMB 9.0, SpecE8 program). As a result of the calculation, the average value logKsp[Al<sub>2</sub>(SeO<sub>3</sub>)<sub>3</sub>⋅6H<sub>2</sub>O] = –28.3 ± 0.5 was obtained. An Eh–pH diagram is constructed for the Al–Se–H<sub>2</sub>O system, which was used to analyze the stability of alfredopetrovite in near-surface conditions.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"14 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139755662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-07DOI: 10.1134/s1075701523070085
R. K. Rastsvetaeva, N. V. Chukanov, I. V. Pekov, M. F. Vigasina
Abstract
The chemical composition, crystal structure, and characteristics of the Raman spectrum of a highly hydrated aqualite-like mineral of the eudialyte group from the Kovdor massif (Kola Peninsula, Russia), in which potassium and hydronium group H3O+ are the species-defining extraframework cations, are studied. The simplified formula of the mineral is (H3O)8Na5K2Zr3Ca6[Si24O69(OH)3][Si2]Mn(OH)2Cl·2H2O. It is characterized by space group R3 and unit-cell parameters a = 14.184(1), c = 30.797(1) Å, V = 5366.27(1) Å3. A specific feature of this mineral, which distinguishes it from all other representatives of the eudialyte group, is a high degree of order in the distribution of large extraframework cations (Na+, K+, Sr2+, Ba2+, Ln3+, and H3O+) over split sites of the crystal structure. In the studied mineral, some oxonium ions form complexes with water molecules with extremely strong hydrogen bonds similar to those that are realized in proton hydrate complexes such as Zundel and Eigen cations.
摘要 研究了科夫多尔地块（俄罗斯科拉半岛）出产的一种高度水合含水岩类乌云石矿物的化学成分、晶体结构和拉曼光谱特征，其中钾和氢基团 H3O+ 是该矿物的决定性框架外阳离子。该矿物的简化公式为 (H3O)8Na5K2Zr3Ca6[Si24O69(OH)3][Si2]Mn(OH)2Cl-2H2O。它的空间群为 R3，单胞参数为 a = 14.184(1)，c = 30.797(1)埃，V = 5366.27(1)埃3。该矿物有别于所有其他柘榴石族代表矿物的一个特点是，框架外大阳离子（Na+、K+、Sr2+、Ba2+、Ln3+ 和 H3O+）在晶体结构分裂位点上的分布具有高度有序性。在所研究的矿物中，一些羰基离子与水分子形成络合物，其氢键极强，类似于质子水合物络合物（如 Zundel 和 Eigen 阳离子）中的氢键。
{"title":"Crystal-Chemical Features of a Cation-Ordered Potassium Analog of Aqualite from the Kovdor Massif (Kola Peninsula)","authors":"R. K. Rastsvetaeva, N. V. Chukanov, I. V. Pekov, M. F. Vigasina","doi":"10.1134/s1075701523070085","DOIUrl":"https://doi.org/10.1134/s1075701523070085","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The chemical composition, crystal structure, and characteristics of the Raman spectrum of a highly hydrated aqualite-like mineral of the eudialyte group from the Kovdor massif (Kola Peninsula, Russia), in which potassium and hydronium group H<sub>3</sub>O<sup>+</sup> are the species-defining extraframework cations, are studied. The simplified formula of the mineral is (H<sub>3</sub>O)<sub>8</sub>Na<sub>5</sub>K<sub>2</sub>Zr<sub>3</sub>Ca<sub>6</sub>[Si<sub>24</sub>O<sub>69</sub>(OH)<sub>3</sub>][Si<sub>2</sub>]Mn(OH)<sub>2</sub>Cl·2H<sub>2</sub>O. It is characterized by space group <i>R</i>3 and unit-cell parameters <i>a</i> = 14.184(1), <i>c</i> = 30.797(1) Å, <i>V</i> = 5366.27(1) Å<sup>3</sup>. A specific feature of this mineral, which distinguishes it from all other representatives of the eudialyte group, is a high degree of order in the distribution of large extraframework cations (Na<sup>+</sup>, K<sup>+</sup>, Sr<sup>2+</sup>, Ba<sup>2+</sup>, Ln<sup>3+</sup>, and H<sub>3</sub>O<sup>+</sup>) over split sites of the crystal structure. In the studied mineral, some oxonium ions form complexes with water molecules with extremely strong hydrogen bonds similar to those that are realized in proton hydrate complexes such as Zundel and Eigen cations.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"4 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139755665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-07DOI: 10.1134/s1075701523070097
S. G. Skublov, A. O. Krasotkina, A. B. Makeyev, O. L. Galankina
Abstract
The distribution of trace elements (secondary ion mass spectrometry method) in rutile from the Yarega oil–titanium deposit was studied for the first time. A significant difference in the composition in the series leucoxene–rutile leucoxene (rutile with microscopic quartz inclusions)–rutile (recrystallized crystals) was established. Leucoxene is characterized by increased contents of the following elements (average values): Al (20 650 ppm), Fe (4833 ppm), Nb (2229 ppm), Zr (1273 ppm), Cr (436 ppm), V (1191 ppm), Sn (230 ppm), W (130 ppm), and Th (125 ppm). As leucoxene is converted to rutile leucoxene, represented by rutile with numerous quartz inclusions, a decrease in the contents of almost all trace elements, with the exception of V, was recorded. The Fe content decreases to 1892 ppm, that of Al to 1468 ppm, of Nb to 605 ppm, of Zr to 409 ppm, of Sn to 46 ppm, and of Cr to 181 ppm. A separate group is represented by rutile grains, in which one can observe a combination of rutile with numerous inclusions of quartz and “pure” rutile (recrystallized rutile with inclusions). The main trend in the change in the composition of rutile is a significant decrease in contents of a number of trace elements, compared with leucoxene and rutile leucoxene: the average V content is 71 ppm in rutile, 2.5 ppm in Sn, 144 ppm in Zr, 2.4 ppm in Hf, 52 ppm in Cr, and 677 ppm in Fe. There is also a decrease in Sb, Th, and U contents to about 1 ppm. There is a tendency toward accumulation of Nb when comparing rutile leucoxene and “pure” rutile. One can assume that the purification of rutile from admixtures as rutile leucoxene is transformed into sites of “pure” rutile (anatase?), up to the formation of single idiomorphic rutile crystals is a consequence of the hydrothermal process previously recorded in the geochemical characteristics of zircons from the Yarega deposit.
{"title":"Trace-Element Composition of Titanium Phases of Leucoxene–Quartz Ores from the Yarega Oil–Titanium Deposit, South Timan","authors":"S. G. Skublov, A. O. Krasotkina, A. B. Makeyev, O. L. Galankina","doi":"10.1134/s1075701523070097","DOIUrl":"https://doi.org/10.1134/s1075701523070097","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The distribution of trace elements (secondary ion mass spectrometry method) in rutile from the Yarega oil–titanium deposit was studied for the first time. A significant difference in the composition in the series leucoxene–rutile leucoxene (rutile with microscopic quartz inclusions)–rutile (recrystallized crystals) was established. Leucoxene is characterized by increased contents of the following elements (average values): Al (20 650 ppm), Fe (4833 ppm), Nb (2229 ppm), Zr (1273 ppm), Cr (436 ppm), V (1191 ppm), Sn (230 ppm), W (130 ppm), and Th (125 ppm). As leucoxene is converted to rutile leucoxene, represented by rutile with numerous quartz inclusions, a decrease in the contents of almost all trace elements, with the exception of V, was recorded. The Fe content decreases to 1892 ppm, that of Al to 1468 ppm, of Nb to 605 ppm, of Zr to 409 ppm, of Sn to 46 ppm, and of Cr to 181 ppm. A separate group is represented by rutile grains, in which one can observe a combination of rutile with numerous inclusions of quartz and “pure” rutile (recrystallized rutile with inclusions). The main trend in the change in the composition of rutile is a significant decrease in contents of a number of trace elements, compared with leucoxene and rutile leucoxene: the average V content is 71 ppm in rutile, 2.5 ppm in Sn, 144 ppm in Zr, 2.4 ppm in Hf, 52 ppm in Cr, and 677 ppm in Fe. There is also a decrease in Sb, Th, and U contents to about 1 ppm. There is a tendency toward accumulation of Nb when comparing rutile leucoxene and “pure” rutile. One can assume that the purification of rutile from admixtures as rutile leucoxene is transformed into sites of “pure” rutile (anatase?), up to the formation of single idiomorphic rutile crystals is a consequence of the hydrothermal process previously recorded in the geochemical characteristics of zircons from the Yarega deposit.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"200 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139755676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-07DOI: 10.1134/s1075701523070073
L. A. Pautov, A. A. Agakhanov, I. V. Pekov, V. Yu. Karpenko, O. I. Siidra, E. V. Sokolova, F. C. Hawthorne, A. R. Fayziev
Abstract
A new trioctahedral mica garmite, CsLiMg2(Si4O10)F2, a Cs analogue of tainiolite, was found in an substantially quartz rock in the Darai-Pioz alkaline massif, Rasht district (formerly Garm district), Central Tajikistan, and was named after the town Garm, an administrative center of the Rasht district. It is closely associated with Mn-bearing pectolite, aegirine, Sr-rich fluorite, quartz, datolite, and polylithionite. Garmite forms lamellae up to 0.2 mm across and up to 0.02 mm thick. The mineral is transparent, colorless, with perfect, mica-like cleavage on (001). The Moh’s hardness is 2.5; micro-indentation hardness VHN20 = 90 kg/mm2. Dmeas = 3.34(2) and Dcalc = 3.336 g/cm3. Garmite is optically biaxial (–), 2Vmeas = –10(5)°, α = 1.582(2), β = 1.601(2), γ = 1.602(2). The chemical composition (electron microprobe, Li and H by SIMS, wt %): SiO2 47.39, Al2O3 0.71, TiO2 0.71, Nb2O5 0.12, FeO 2.12, MnO 0.85, MgO 9.01, ZnO 2.23, K2O 0.16, Cs2O 26.98, Li2O 3.57, H2O 0.08, F 7.23, –O=F2 3.04, total 99.90. The empirical formula calculated on the basis of 12 (O + F) apfu is (Cs0.95K0.02)Σ0.97Li1.21(Mg1.37Zn0.16Fe0.15Al0.07Mn0.06Ti0.04)Σ1.85Si3.99O10.04(F1.92OH0.04)Σ1.96. Garmite is monoclinic, space group C2/m, C2 or Cm; polytype 1M. The unit-cell parameters are a = 5.234(2), b = 9.042(4), c = 10.780(4) Å, β = 99.73(4)°; V = 502.8(6) Å3; Z = 2. The strongest reflections of the powder X‑ray diffraction pattern (d Å, I, hkl) are 4.48, 35, 110; 3.70, 70, –112; 3.45, 44, 022; 2.608, 70, –201, 130; 2.580, 100, 200, –131; 2.241, 45, 220; 2.187, 80, –133. The holotype specimen is deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow catalogue no. 95894.
{"title":"Garmite, CsLiMg2(Si4O10)F2, a New Mica-Group Mineral from “Quartz Blocks” of the Darai-Pioz Alkaline Massif, Tajikistan","authors":"L. A. Pautov, A. A. Agakhanov, I. V. Pekov, V. Yu. Karpenko, O. I. Siidra, E. V. Sokolova, F. C. Hawthorne, A. R. Fayziev","doi":"10.1134/s1075701523070073","DOIUrl":"https://doi.org/10.1134/s1075701523070073","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A new trioctahedral mica garmite, CsLiMg<sub>2</sub>(Si<sub>4</sub>O<sub>10</sub>)F<sub>2</sub>, a Cs analogue of tainiolite, was found in an substantially quartz rock in the Darai-Pioz alkaline massif, Rasht district (formerly Garm district), Central Tajikistan, and was named after the town Garm, an administrative center of the Rasht district. It is closely associated with Mn-bearing pectolite, aegirine, Sr-rich fluorite, quartz, datolite, and polylithionite. Garmite forms lamellae up to 0.2 mm across and up to 0.02 mm thick. The mineral is transparent, colorless, with perfect, mica-like cleavage on (001). The Moh’s hardness is 2.5; micro-indentation hardness VHN<sub>20</sub> = 90 kg/mm<sup>2</sup>. <i>D</i><sub>meas</sub> = 3.34(2) and <i>D</i><sub>calc</sub> = 3.336 g/cm<sup>3</sup>. Garmite is optically biaxial (–), 2<i>V</i><sub>meas</sub> = –10(5)°, α = 1.582(2), β = 1.601(2), γ = 1.602(2). The chemical composition (electron microprobe, Li and H by SIMS, wt %): SiO<sub>2</sub> 47.39, Al<sub>2</sub>O<sub>3</sub> 0.71, TiO<sub>2</sub> 0.71, Nb<sub>2</sub>O<sub>5</sub> 0.12, FeO 2.12, MnO 0.85, MgO 9.01, ZnO 2.23, K<sub>2</sub>O 0.16, Cs<sub>2</sub>O 26.98, Li<sub>2</sub>O 3.57, H<sub>2</sub>O 0.08, F 7.23, –O=F<sub>2</sub> 3.04, total 99.90. The empirical formula calculated on the basis of 12 (O + F) apfu is (Cs<sub>0.95</sub>K<sub>0.02</sub>)<sub>Σ0.97</sub>Li<sub>1.21</sub>(Mg<sub>1.37</sub>Zn<sub>0.16</sub>Fe<sub>0.15</sub>Al<sub>0.07</sub>Mn<sub>0.06</sub>Ti<sub>0.04</sub>)<sub>Σ1.85</sub>Si<sub>3.99</sub>O<sub>10.04</sub>(F<sub>1.92</sub>OH<sub>0.04</sub>)<sub>Σ1.96</sub>. Garmite is monoclinic, space group <i>C</i>2/<i>m</i>, <i>C</i>2 or C<i>m</i>; polytype 1<i>M.</i> The unit-cell parameters are <i>a</i> = 5.234(2), <i>b</i> = 9.042(4), <i>c</i> = 10.780(4) Å, β = 99.73(4)°; <i>V</i> = 502.8(6) Å<sup>3</sup>; <i>Z</i> = 2. The strongest reflections of the powder X‑ray diffraction pattern (<i>d</i> Å, <i>I</i>, <i>hkl</i>) are 4.48, 35, 110; 3.70, 70, –112; 3.45, 44, 022; 2.608, 70, –201, 130; 2.580, 100, 200, –131; 2.241, 45, 220; 2.187, 80, –133. The holotype specimen is deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow catalogue no. 95894.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"37 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139762977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-09DOI: 10.1134/s1075701523060053
P. A. Ignatov, R. U. Eremenko, A. V. Tolstov, I. M. Ovchinnikov
Abstract
In the Malo-Botuobinsky, Sredne-Markhinsky, and Ygyattinsky diamond-bearing areas of the Western Yakutian kimberlite province, the prerequisites and signs of scandium deposits in ancient weathering crusts overlying Lower Paleozoic rocks and associated with zones of ancient reservoir and soil oxidation. According to X-ray fluorescence and ICP MS analyses, in the Nakyn kimberlite field of the Sredne-Markhinsky diamond-bearing region, promising ore occurrences and scandium concentration halos have been established in clay deposits of redeposited weathering crusts of the Dyakhtar Formation of Late Triassic–Early Jurassic age. They are confined to the erosional surface of Lower Paleozoic carbonate rocks and Middle Paleozoic traps, with monzonite porphyries and kimberlites cutting through them, covered on top by a sedimentary cover of Jurassic terrigenous deposits. Concentration anomalies of scandium in clays of the Dyakhtar Formation are localized mainly in deluvial clay deposits of paleowatersheds and gravitate to the intersections of tectonic disturbances. The depth of their occurrence does not exceed 100 m, which is quite favorable for the extraction of scandium by borehole in situ leaching. Concentrations of scandium were detected at one of the sites before 262 g/t in Late Triassic weathering crust, including material from a Middle Paleozoic gabbro dike, as well as overlying colluvial clays of the Dyakhtar formations with a maximum of 462 g/t.
{"title":"Scandium Ore Occurrences in the Ancient Weathering Crust in the Nakyn Kimberlite Field of Yakutia","authors":"P. A. Ignatov, R. U. Eremenko, A. V. Tolstov, I. M. Ovchinnikov","doi":"10.1134/s1075701523060053","DOIUrl":"https://doi.org/10.1134/s1075701523060053","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>In the Malo-Botuobinsky, Sredne-Markhinsky, and Ygyattinsky diamond-bearing areas of the Western Yakutian kimberlite province, the prerequisites and signs of scandium deposits in ancient weathering crusts overlying Lower Paleozoic rocks and associated with zones of ancient reservoir and soil oxidation. According to X-ray fluorescence and ICP MS analyses, in the Nakyn kimberlite field of the Sredne-Markhinsky diamond-bearing region, promising ore occurrences and scandium concentration halos have been established in clay deposits of redeposited weathering crusts of the Dyakhtar Formation of Late Triassic–Early Jurassic age. They are confined to the erosional surface of Lower Paleozoic carbonate rocks and Middle Paleozoic traps, with monzonite porphyries and kimberlites cutting through them, covered on top by a sedimentary cover of Jurassic terrigenous deposits. Concentration anomalies of scandium in clays of the Dyakhtar Formation are localized mainly in deluvial clay deposits of paleowatersheds and gravitate to the intersections of tectonic disturbances. The depth of their occurrence does not exceed 100 m, which is quite favorable for the extraction of scandium by borehole in situ leaching. Concentrations of scandium were detected at one of the sites before 262 g/t in Late Triassic weathering crust, including material from a Middle Paleozoic gabbro dike, as well as overlying colluvial clays of the Dyakhtar formations with a maximum of 462 g/t.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"6 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139412856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-09DOI: 10.1134/s1075701523060090
I. N. Solodov, M. V. Nesterova
Abstract
A generalization of unpublished and published data since 1985 on biogeochemical, hydrogeochemical, geochemical, mineralogical studies and soil geochemistry at uranium deposits of the Khiagda ore field in the Vitim uranium ore district made it possible to reveal a genetic relation of deep cold carbonated hydrocarbonate–magnesium groundwater containing dissolved hydrocarbons (HCs) to uranium mineralization and ore preservation. The through penetration of epigenetic HCs was traced from the disintegration zone of basement granitoids through overlying sedimentary ore-bearing and volcanosedimentary rocks up to overlying fractured basalts. The assemblage of clarified rocks–HCs–siderites–uranium phosphates U(IV) was commonly found. Carbonated hydrocarbonate–magnesium groundwater and anomalous HC contents in soils can be additional criteria for identifying the Vitim-type uranium deposits in the Trans-Baikal region.
{"title":"Occurrence of Carbonated Groundwater and Hydrocarbons at the Uranium Deposits of the Khiagda Ore Field (Republic of Buryatia)","authors":"I. N. Solodov, M. V. Nesterova","doi":"10.1134/s1075701523060090","DOIUrl":"https://doi.org/10.1134/s1075701523060090","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A generalization of unpublished and published data since 1985 on biogeochemical, hydrogeochemical, geochemical, mineralogical studies and soil geochemistry at uranium deposits of the Khiagda ore field in the Vitim uranium ore district made it possible to reveal a genetic relation of deep cold carbonated hydrocarbonate–magnesium groundwater containing dissolved hydrocarbons (HCs) to uranium mineralization and ore preservation. The through penetration of epigenetic HCs was traced from the disintegration zone of basement granitoids through overlying sedimentary ore-bearing and volcanosedimentary rocks up to overlying fractured basalts. The assemblage of clarified rocks–HCs–siderites–uranium phosphates U(IV) was commonly found. Carbonated hydrocarbonate–magnesium groundwater and anomalous HC contents in soils can be additional criteria for identifying the Vitim-type uranium deposits in the Trans-Baikal region.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"39 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139412896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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