Mineralogical Journal-Ukraine最新文献

{"title":"LITHIUM ORES OF STANKUVATKA AND POLOKHIVKA ORE FIELDS (UKRAINIAN SHIELD)","authors":"V. Syomka, O. Ponomarenko, L. Stepanyuk, S. Bondarenko, V. Sukach, S. Kurylo, M.O. Donskyi","doi":"10.15407/mineraljournal.44.04.102","DOIUrl":"https://doi.org/10.15407/mineraljournal.44.04.102","url":null,"abstract":"New results of mineralogic-petrographical and ore-geochemical research on Li-pegmatites and host rocks of Stankuvatka and Polokhivka ore fields of western part of Inhul megablock of the Ukrainian Shield are presented. Petrographic characteristics of host rocks, such as granites, metapelites, metabasites and ultrabasites are described. Aplite-pegmatoid granites related to Li-pegmatites have been dated as 2026-2042 Ma by means of U-Pb isotopic analysis of monazites. Li-pegmatites were formed during two stages: 1) magmatic, when formation of oreless quartz-albite-microcline pegmatites happened; 2) hydothermal-metasomatic, when residual fluid rich in rare elements affects previously formed minerals; it is reflected in presence of several generations of Li-bearing and rock-forming minerals. Initial magma was peraluminous, depleted with mafic components, and with water deficit. Albite was a first mineral crystallized in researched pegmatites. Then albite+quartz were crystallized. Then at the end microcline+quartz were formed in the central part of pegmatite veins. Petalite and spodumene were formed at the final hydrothermal-metasomatic stage. Practical importance of ores with secondary mineralization mainly presented with petalite and spodumene has been defined. Petalite ore type of Polokhivka deposit and petalite-spodumene mixed ore type of Stankuvatka deposit have a crucial role. Microprobe chemical analysis of accessory mineralization presented with triphylite, montebrasite, and other Lithium phosphates has been carried out. These minerals were detected in pegmatites and in metasomatically altered host rocks. They can be reliable criteria during geological exploration of Lithium at other locations of Shpola-Tashlyk ore district.","PeriodicalId":53834,"journal":{"name":"Mineralogical Journal-Ukraine","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67127122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"AGE OF THE HANNIVKA GRANITE (MIDDLE-DNIEPER MEGABLOCK OF THE UKRAINIAN SHIELD)","authors":"G. Artemenko, L. Shumlyanskyy, I. Shvaika, V. Butyrin","doi":"10.15407/mineraljournal.44.04.073","DOIUrl":"https://doi.org/10.15407/mineraljournal.44.04.073","url":null,"abstract":"The Middle-Dnieper megablock, which is a fragment of the craton, differs from other cratons found on Earth. This is because of the large variety of granitoids (Tokiv, Mokro-Moskowka, and Demuryne complexes) in the former that were formed after the Mesoarchean TTG. Thus, the Middle-Dnieper megablock is important for studying the genesis and geodynamic formation conditions of Late Archaean granitoids. The granitoids in the Middle-Dnieper megablock are not well understood. They include the Hannivka granites of the East Hannivka monocline of the Kryvyi Rih-Kremenchuk structure, whose age and stratigraphic position has been a matter of a long-standing debate. The purpose of the work is to study the geochemistry, genesis and U-Pb age of the Hannivka granites. Based on our results, the Hannivka granites possibly formed in the crust resulting from the melting of older rocks. They differ from other Late Archean granitoids of the Middle-Dnieper megablock by their high U (56.4 ppm) content and the presence of Mo (4.3 ppm). The Hannivka granites underwent tectonic reworking during a collisional event about 2.0 billion years ago, which is probably associated with the kalishpatization of these rocks. The U-Pb age of the cores of zircons sampled from the Hannivka granites, determined by LA-ICP-MS method, are about 2827±16 million years in age. Younger rims probably formed during kalishpatization. The Hannivka granites are the same age as the granitoids of the Mokro-Moskowka and Tokiv complexes. Late Archean granitoids were formed between 2.99-2.7 Ga in the Middle-Dnieper granite-greenstone block and in the geologically similar granite-greenstone block KMA are 2.6 Ga in age. In the Pilbara craton, which is a Paleoarchean granite-greenstone complex, the age of biotite and feldspar granites is similar to the age of the rocks on the Middle-Dnieper megablock (2.94-2.93 Ga). The difference in magmatism ages may be due to the drift of the different cratons above mantle plumes of different ages.","PeriodicalId":53834,"journal":{"name":"Mineralogical Journal-Ukraine","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67126825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Water-Rich Melt Inclusion as \"Frozen\" Samples of the Supercritical State in Granites and Pegmatites Reveal Extreme Element Enrichment Resulting Under Non-Equilibrium Conditions","authors":"R. Thomas, P. Davidson, A. Rericha, D. Voznyak","doi":"10.15407/mineraljournal.44.01.003","DOIUrl":"https://doi.org/10.15407/mineraljournal.44.01.003","url":null,"abstract":"In this contribution, we show that in miarolitic pegmatites during the crystallization of water-rich melts, samples of these mineral-forming melts were trapped in the form of water-rich melt inclusions, preserved primarily in quartz. The bulk concentration of water and the temperature are the system-determining parameters since from their analysis it follows that these melt inclusions depict pseudo-binary solvus curves in the coordinates of temperature and water concentration. Furthermore, using reduced coordinates (H2O/H2Ocrit vs. T/Tcrit) most melt inclusions of the studied pegmatites plot very well in a standardized and reduced solvus curve. The existence and formation of such uniform solvus curves is an expression of crystallization processes under nearly equilibrium conditions. However, many trace and some principal elements of the melt inclusions trapped near the solvus crest [H2O/H2Ocrit from 0.5 to 1.5 and T/Tcrit > 0.95] show unusual distributions, with very well-defined Gaussian and/or Lorentzian curves, characterized by defined area, width, offset, and height. This has been shown in many natural examples obtained from pegmatites. Only the offset values represent near-equilibrium conditions and corresponding element concentrations, which are equivalent to the regional Clarke number (Clarke number or Clark is the relative abundance of a chemical element, typically in the Earth's crust). We interpret these distributions as explanation for some extraordinary-chemical properties in this critical region: principally extremely high diffusion rates, low dynamic viscosity and extremely low surface tension. Near the critical point, we have both space and time-related non-equilibrium and equilibrium processes close together. Furthermore, we can show that the Gaussian and Lorentzian distribution are first approximations of the specific element distribution because at the critical point the enrichment of some elements reaches such an extent that the Gaussian and/or Lorentzian curves degenerate into a vertical line (are asymptotic to the concentration axis), which is determined by the maximum solubility of a species in the supercritical melt-water system. The highest concentration of Be, as an example, was observed in Ehrenfriedersdorf melt inclusions: 71490 ppm Be.","PeriodicalId":53834,"journal":{"name":"Mineralogical Journal-Ukraine","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67126475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"URANIUM-LEAD GEOCHRONOLOGY BY TITANITE, ADVANTAGES AND LIMITATIONS","authors":"L. Stepanyuk, T. Dovbush, O. Vysotsky, V. Belsky, O. Zyultsle, T.B. Yaskevich, I. Kotvitska","doi":"10.15407/mineraljournal.44.03.083","DOIUrl":"https://doi.org/10.15407/mineraljournal.44.03.083","url":null,"abstract":"The uranium-lead isotope method is used to date titanites from granitoids of the Ros'-Tikych megablock of the Ukrainian Shield (middle reaches of the Ros' river, below Bila Tserkva). Their isotopic behavior is analyzed along with published results, of other titanites found in crystalline rocks of the Ukrainian Shield. Titanites of granitoids from the Ros'-Tikych megablock contain impurity lead and this leads to an abnormal isotopic composition. The overestimation in age values calculated by methods that do not require correction for ordinary lead (method normalized, agreed differences and the slope of the regression line on the graph in the coordinates 207Pb/204Pb — 206Pb/204Pb) is up to several tens of millions of years, compared to, calculated on the model of Ahrens-Wetherill. The influence of impurity lead of anomalous isotopic composition on the distortion of the calculated values of the isotopic age, in the ratio 207Pb/206Pb is modeled. It was found that the entry into the isotope system, 2.0 billion years old, of ordinary lead with a modern isotopic composition, even with a ratio of impurity lead to radiogenic lead 1:1, will reduce the age by 207Pb/206Pb by only 4 million years. Significantly greater distortions (overestimations) of the isotopic ages is will be caused by impurity lead, in the isotopic composition of which there is an ancient (for example, 500 million older than the age of crystallization of titanite) radiogenic lead. Thus, when the ratio share of impurity lead is 20%, the overestimation of age is more than 50 million years, and it reaches 235 million years forat a ratio of 1:1 (50%). The numerical values of the isotopic age will be even more inflated at the ratio of 207Pb/206Pb in cases when impurity lead contains radiogenic lead of older age, even with a smaller share of it in the composition of impurity lead.","PeriodicalId":53834,"journal":{"name":"Mineralogical Journal-Ukraine","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67126602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THERMOBAROGEOCHEMICAL EXPLORATION AND ASSESSMENT CRITERIA OF GOLD MINERALIZATION OF THE BALKA SHYROKA DEPOSIT (MIDDLE DNIEPER REGION)","authors":"M. Pavlun, H. Hotsaniuk, A. Ivanina","doi":"10.15407/mineraljournal.44.03.111","DOIUrl":"https://doi.org/10.15407/mineraljournal.44.03.111","url":null,"abstract":"A scheme of the staging and thermobaric regime of the formation of the Balka Shyroka deposit gold mineralization (Middle Dnieper megablock of the Ukrainian Shield) was constructed, and the sequence and thermobaric intervals of ore formation were determined. Mineral paragenesises are combined into four mineral associations that form a series of mineral complexes: pre-productive magnetite-quartz, productive polysulphide, which includes two productive gold-bearing associations (arsenopyrite-pyrite-quartz with gold and gold-sulphosalt) and post-productive carbonate (quartz-calcite mineral association). Gold-producing associations were formed in a rather narrow range of temperature and pressure changes of the ore-forming environment specific to its composition and aggregate-density state. This affected the phase typomorphism of the respective families of fluid inclusions. Carbon dioxide-water inclusions with different phase ratios are common: Г—РСО2—РН2О, РСО2—Г—РН2О, РСО2—РН2О, Г—РСО2. The most optimal temperature for homogenization of gas-liquid inclusions (according to the first type) is 210-290 °С. In minerals, there are families of two-phase and one-phase CO2 fluid inclusions with wide variations in its density (from 0.65 to 0.87 g/cm3) and homogenization into the liquid phase. These typomorphic features are thermobarogeochemical search criteria and evaluation signs of gold mineralization. Equally important is the definition of the paleotemperature gradient and the spatial extrapolation of its change with depth, which makes it possible to calculate the vertical extent of mineralization, the level of its erosional section, and the depth of thinning out.","PeriodicalId":53834,"journal":{"name":"Mineralogical Journal-Ukraine","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67126665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EVIDENCES OF WEATHERING OF IRON-NICKEL AND TROILITE IN THE GRUZ'KE Н4-TYPE CHONDRITE","authors":"S. Shyrinbekova","doi":"10.15407/mineraljournal.44.02.011","DOIUrl":"https://doi.org/10.15407/mineraljournal.44.02.011","url":null,"abstract":"Terrestrial weathering of the Gruz'ke chondrite was investigated by considering its initial chemical, structural, and mineralogical characteristics. The spread of corrosion and degree of alteration were related to the high content of Fe-Ni metal, the phase inhomogeneity and the different concentration of Ni in the metal, as well as, the shock metamorphism features, and the residence time of the meteorite sample in a soil environment. The formation of secondary oxide veins and oxide rims, consisting of iron hydroxide pseudomorphs was caused by the selective corrosion of kamacite α-(Fe,Ni), compared to taenite γ-(Fe,Ni) and troilite FeS. A spatial relationship between shock metamorphism features, namely areas of plastic deformation, shock heating and weathering of the meteorite matter, has been confirmed. A secondary Ni-enriched phase, which contains 71.34 to 72.94 wt.% Ni, probably corresponds to awaruite (Ni2Fe to Ni3Fe) or native nickel. This phase is described for the first time as corrosion product of Fe-Ni grains in the Gruz'ke chondrite. We assume that this phase was formed during the alteration of Fe-Ni metal. Fe was removed from the meteorite metal during the corrosion process, while sulfur was introduced. The formation of iron hydroxide pseudomorphs caused changes in primary chemical and structural properties of some crystals of nickel-iron metal and troilite. Thus, the use of weathered mineral grains to interpret the pre-terrestrial conditions of the chondrite matter formation and evolution is limited. In spite of the changes in chemical and mineral composition, the corrosion products of nickel iron and troilite have consistent low chlorine content.Therefore we assume that the akaganeite β-FeO(OH,Cl) secondary phase is unlikely to form. It will prevent further alteration of the Fe-Ni metal and ensure long-term storage and preservation of the meteorite sample for further laboratory research and storage in the museum collection.","PeriodicalId":53834,"journal":{"name":"Mineralogical Journal-Ukraine","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67126805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THE HISTORY OF MINERALOGY IN THE WORKS OF ACADEMICIAN YEVHEN LAZARENKO, HIS STUDENTS AND FOLLOWERS (To the 110th Anniversary of the Scientist's Birth)","authors":"O. Matkovskyi, Ye. M. Slyvko","doi":"10.15407/mineraljournal.44.04.140","DOIUrl":"https://doi.org/10.15407/mineraljournal.44.04.140","url":null,"abstract":"The mineralogical science history occupies a prominent place in academician Ye. Lazarenko's scientific and pedagogical works: in monographic summaries of regional and genetic mineralogy, five editions of the textbook \"Course of Mineralogy\", the famous \"Mineralogical Dictionary\". A number of separate articles (individual or with co-authors) are devoted to the history of mineralogy in general and Ukraine in particular. Not all of the scientist's ideas were realized during his lifetime, but students and followers of Yevhen Kostiantynovych — representatives of the scientific mineralogical school that bears his name, a member of the Ukrainian Mineralogical Society, try to continue the work of their teacher. Various aspects of the history of the development of mineralogical research are covered in specialized publications — \"Mineralogical Collection\", \"Mineralogical Journal\", \"Proceedings of the Ukrainian Mineralogical Society\". They are discussed at scientific readings named after Academician Ye. Lazarenko, congresses of the Ukrainian Mineralogical Society and other scientific forums. The separate chapters in modern textbooks, educational aids, reference publications are devoted to the history of mineralogical development in Ukraine and in general; in recent years a number of specialized monographic publications were published.","PeriodicalId":53834,"journal":{"name":"Mineralogical Journal-Ukraine","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67127220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PETROLOGY OF CENOZOIC DYKES ON THE ARGENTINE ISLANDS (WILHELM ARCHIPELAGO, WEST ANTARCTICA)","authors":"O. Mytrokhyn, L. Gavryliv, V. Bakhmutov","doi":"10.15407/mineraljournal.44.03.067","DOIUrl":"https://doi.org/10.15407/mineraljournal.44.03.067","url":null,"abstract":"Dyke swarms that intrude Paleogene granitoids of the Argentine Islands near the Ukrainian Antarctic Station \"Akademik Vernadsky\" were studied. The field relations and mineralogical, petrographical and geochemical properties of the dykes allow their relative geological age and the geodynamic conditions to be clarified. The magmatic activity in the study area did not cease, at least until the end of the Miocene when the processes of orogenic uplift led to the erosive exposure of the Paleogene granitoids of the Barchans-Forge Massif. Tectonic exhumation of the latter was accompanied by the intrusion of dykes of different compositions at different depths. Cenozoic basalt and diabase dykes are the most common. Most are subvolcanic fractured intrusions formed after the complete exhumation of the host granitoids, which ended by the Miocene (11 Ma). The basaltic dykes are probably one of the youngest representatives of magmatism in the region. They have an intermediate position between high-LILE tholeiites and the calc-alkaline series. However, the nature of contamination of the basaltic dykes by crustal rocks requires additional research. Cenozoic microdiorites dykes are rarer than basaltic ones. They are hypabyssal fractured intrusions formed during the tectonic exhumation of the Barchans-Forge granitoids between the beginning of the Paleocene and the end of the Miocene (61-11 Ma). The microdiorites belong to the orogenic calc-alkaline series and they could be related to subduction processes. The discovery of only one dacite dyke indicates the rarity of acid magmatism during the Cenozoic period. It occurs as a fractured intrusion and formed after the exhumation of the host granitoids. The dacite dyke belongs to the calc-alkaline series, which, along with other compositional properties, suggests that dacite and microdiorite dykes are comagmatic.","PeriodicalId":53834,"journal":{"name":"Mineralogical Journal-Ukraine","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67126562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GEOCHEMICAL CHARACTERISTICS OF THE MAIN ROCKS TYPES OF THE KORSUN'-NOVOMYRHOROD ANORTHOSITE-RAPAKIVI GRANITE PLUTON","authors":"O. Dubyna, S. Kryvdik, I. Shvaika, I. Shvaika, P. Yakubenko, L. Proskurka","doi":"10.15407/mineraljournal.44.01.020","DOIUrl":"https://doi.org/10.15407/mineraljournal.44.01.020","url":null,"abstract":"The geochemical features of most distributed rocks from the Korsun'-Novomyrhorod Pluton are considered. The obtained data give reason to assume that the association of basic and intermediate rocks of the pluton was formed because of the differentiation of the primary melt, similar in composition to high alumina tholeiites. It can be inferred that anorthosites were the earliest rocks that appeared in the early stages of plagioclase crystallization. The chondrite-normalized patterns of REE from anorthosites are characterized by the classical distribution of REE for such rocks, with significant positive Eu-anomalies at low REE concentrations. Further evolution of the residual melts enriched by mafic components could lead to the formation of gabbro-anorthosites. Less distributed gabbronorites and norites were formed because of crystallization of residual melts after segregation of anorthositic and gabbro-anorthositic cumulates. Considering the high iron content in all types of rocks, the basic rocks crystallized from residual melts that were genetically related to anorthosites. But ore-bearing norites (Nosachiv-type), in contrast to most distributed basic rocks, had been formed in the early stages because of simultaneous accumulation of feldspar and ilmenite, followed by gravitational precipitation at lower levels of magmatic chambers. The genesis of monzonite-syenite rocks is more enigmatic. Their geochemical features very resemble those in gabbroic rocks, which gives reason to consider them as a result of residual melts crystallization after escaping from anorthositic and gabbronoritic bodies. Subsequent migration and protracted differentiation of such K-enriched melts could cause the appearance of the high-Fe syenites of the Velyka Vyska-type, enriched in REE, Y, Zr, partially Nb, and depleted in Sr and Ba. Although the geochemical characteristics of rapakivi show significant similarities to monzonitic rocks, their genesis remains problematic. It's worth noting that our findings are more consistent with continental crust melting caused by ascending intrusions of basic composition.","PeriodicalId":53834,"journal":{"name":"Mineralogical Journal-Ukraine","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67126576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"STRUCTURAL ENVIRONMENT OF FLUORIDE IONS IN APATITES OF CHEMICAL COMPOSITION AND ORIGIN: 19F MAS NMR STUDY","authors":"O. Kalinichenko, V. Pavlyshyn, V. Snisar, A. Kalinichenko","doi":"10.15407/mineraljournal.44.03.003","DOIUrl":"https://doi.org/10.15407/mineraljournal.44.03.003","url":null,"abstract":"Apatites of markedly different chemical composition and origin were studied using 19F magic-angle spinning nuclear magnetic resonance. Synthetic carbonate fluorapatites (CFAp) containing 2.6 to 4.7 wt% F, 0 to 4 wt% CO2 and 0 to 1 wt% Na2О, hydroxylfluorapatite (OH:F ≈ 1:1) containing about 3 wt% Y (Y-HFAp), natural REE-apatites, and CFAp and Y-HFAp heated at temperature from 700 to 1000 oC were researched. The spectra of apatites with isomorphic substitutions show the signals (chemical shift δ) caused by fluoride ions in fluorapatite structure and, possibly, near defects in Ca sites (from −102.5 to −100 ppm), near water molecules (H2Os) incorporated in the channels (about −96.5 ppm), and one or two signals with δх from −91 to −86 ppm. The spectra of synthetic CFAp and Y-НFAр heated up to 900 oС and original natural REE-apatites show two components, δх1 and δх2 shifted with 2 − 3 ppm, in this range. It is shown that the component δx2 is new, it hasn’t been observed in the spectra previously. Signals in the δх range are caused by Fх ions (up to 12% F) whose structural environment is different substantially from the \"ideal\" fluorapatite structure. It is found that the contents of Fх ions and CO2 in synthetic CFAp correlate linearly. It is shown that Fx (Fх1) ions can occupied sites in the channels near single vacancies Ca, and Fх2 ions — near double vacancies, Ca and anionic those in the channels, in CFAp with the F content not higher than stoichiometric and Y-НFАр. These vacancies can form through different heterovalent isomorphism mechanisms such as РО43− → СО32− and/or Са2+ → M3+ (М = REE, Al, Fe), vacancies in the channels of heated apatites with partial substitutions F → H2Os, OH — through dehydration and/or dehydroxylation.","PeriodicalId":53834,"journal":{"name":"Mineralogical Journal-Ukraine","volume":null,"pages":null},"PeriodicalIF":0.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67126442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}