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Kang, Zhi Qiang, Zuo Hai Feng, Yong Gao Huang, Hong Yi Chen, Wei Fu und Jia Fei Liao. „Mineralogical Study of Huashan Granite-Type Uranium Ore Deposit in Northeast of Guangxi“. Advanced Materials Research 621 (Dezember 2012): 17–22. http://dx.doi.org/10.4028/www.scientific.net/amr.621.17.
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Huashan granite-type uranium ore deposit is originated within the Huashan granite pluton in northeast of Guangxi, the mineral (mineralization) occurrences already found include Changchong, Baishijiao and Caomiping. Previous studies are relatively weak, especially in mineralogical characteristics, in this paper, a detailed study of minerals has been carried out through EPMA and EDS, the results show that the uranium mineral compositions of the three mineral (mineralization) occurrences are significantly different, but all of them are of secondary uranium minerals, among them, the main component of Changchong mineral (mineralization) occurrence is (meta-) autunite, of Baijiaoshi mineral (mineralization) occurrence is kasolite, and of Caomiping mineral (mineralization) occurrence is torbernite and zeunerite, which reflect the difference of their minerals sources.
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Gavryliv, Liubomyr, Vitalii Ponomar, Marko Bermanec und Marián Putiš. „The Taxonomy of Mineral Occurrence Rarity and Endemicity“. Canadian Mineralogist 60, Nr. 5 (01.09.2022): 731–58. http://dx.doi.org/10.3749/canmin.2200010.
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ABSTRACT Nearly a half of known IMA-approved minerals (as of November 2021) are reported from four localities or fewer and so may be considered rare mineral species. These minerals form a continuum with more common species (e.g., rock-forming minerals), all of which constitute important constituents of Earth and contributors to its dynamics. To better understand the taxonomy of mineral rarity, evaluations have been made on the basis of k-means clustering and kernel density estimation of one-dimensional data on mineral occurrence metrics. Results from second- and third-degree polynomial regression analyses indicate the presence of a divergence between the observed number of endemic minerals discovered since 2000 and those that are likely to represent “true” endemic species. The symmetry index, calculated using the approach of Urusov for each rarity cluster, reveals a gradual decrease from ubiquitous to endemic from 0.64 to 0.47. A network analysis of element co-occurrences within each rarity cluster suggests the existence of at least three different communities having similar geochemical affinities; the latter may reflect the relative abundance of minerals their elements tend to form. The analysis of element co-occurrence matrices within each group indicates that crustal abundance is not the only factor controlling the total number of minerals each element tends to form. Other significant factors include: (1) the geochemical affinity to the principal element in the group (i.e., sulfur for chalcophile and oxygen for lithophile elements) and (2) dispersion of the principal element through geochemical processes. There is a positive correlation between the lithophile element group's abundance in the Earth's crust and the number of common minerals they tend to form, but a negative correlation with the number of rare species.
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Vegarud, Gerd E., T. Langsrud und C. Svenning. „Mineral-binding milk proteins and peptides; occurrence, biochemical and technological characteristics“. British Journal of Nutrition 84, S1 (November 2000): 91–98. http://dx.doi.org/10.1017/s0007114500002300.
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Minerals and trace elements in cow's milk occur as inorganic ions and salts or form complexes with proteins and peptides, carbohydrates, fats and small molecules. The main mineral binder or chelators of calcium are the caseins, αs1-casein, αs2-casein, β-casein and κ-casein, but also whey proteins and lactoferrin bind specific minerals like calcium, magnesium, zinc, iron, sodium and potassium. Less documented is the binding of trace elements. Peptides obtained byin vitroorin vivohydrolysis act as mineral trappers through specific and non-specific binding sites. They may then function as carriers, chelators, of various minerals and thus enhance or inhibit bioavailability. Peptides from milk proteins have found interesting new applications in the food industry as products with improved functionality or as ingredients of dietary products, or used in pharmaceutical industry. Fortification of foods with minerals in a low concentration has for a long time been used in some countries to overcome mineral deficiency, which is an increasing problem in humans. These types of foods are being used to create a new generation of super foods in the industry today.
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Oktyabrsky, R. A., S. A. Shcheka, A. M. Lennikov und T. B. Afanasyeva. „The first occurrence of qandilite in Russia“. Mineralogical Magazine 56, Nr. 384 (September 1992): 385–89. http://dx.doi.org/10.1180/minmag.1992.056.384.11.
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AbstractNumerous small octahedra of a black, brittle, magnetic mineral were found in calciphyre and brucite marble, occurring in the northern part of the exocontact zone of the Kondyor ultramafic-alkalic massif (south-eastern part of the Aldan Shield, 250 km north west of sea port Ayan). Their composition corresponds to the group from titanium magnesioferrite (11.53% TiO2) to titanium-rich magnesian spinel (27.34% TiO2), similar to spinellide found in Greenland (Gittins et al., 1982) and in Iraq (Al-Hermezi, 1985) and approved by the Commission on New Minerals as a new mineral named qandilite. Hardness, specific gravity, and reflectance of Kondyor qandilite are similar to those of the Iraq mineral. Peaks of IR-absorption spectra are equal to 580-590 cm−1 (v2) and 431-438 cm−1 (v2). There is a positive correlation between lattice parameters and the amount of Mg2TiO4: from 8.368 Å at 26.6% to 8.429 Å at 60.4%. Kondyor qandilite crystallized together with geikielite, oxidized alumina spinel (8.55% Fe2O3, ftotal : 16.5%), periclase, and forsterite.
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Zhang, Dongwei, Meng Han, Qianshan Zhou, Tianrui Ye, Yujie Zhou, Ji Chang und Xiaohui Lin. „The Micro-Occurrence Mechanisms of Tight Oil: Fluid–Rock Interactions at Microscale Pores, Nanoscale Pores, and Mineral Surfaces“. Energies 16, Nr. 9 (05.05.2023): 3917. http://dx.doi.org/10.3390/en16093917.
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Understanding the micro-occurrence mechanism of tight oil has long been a daunting challenge in the exploration and development of unconventional resources. This article discusses the micro-occurrence mechanism of tight oil through continuous extraction by combining thin casting, fluorescent thin sections, environmental scanning electron microscope observations, physical property testing, and X-ray diffraction experiments. The results indicated that in the tight sandstone of the Chang 8 Formation in the Ordos Basin, the average tight oil content was 35.46% for microscale pores, 35.74% for nanoscale pores, and 28.79% for mineral surfaces. Six types of micro-occurrence states of tight oil were identified: emulsion, cluster, throat, star-like, isolation, and thin film forms. Although clay minerals and heavy components dominate the adsorption of tight oil on mineral surfaces, micro-occurrence is fundamentally an oil–rock interaction process. Hence, oil–rock interactions and occurrence states were combined in this study to identify tight oil’s micro-occurrence mechanism. The van der Waals forces of attraction between asphaltene molecules and a mineral surface play a critical role, and minerals with hydroxyl groups can also combine with carboxyl and hydroxyl groups present in tight oil. As a consequence of the adsorption of heavy components by minerals, tight oil components remain in microscale and nanoscale pores with a higher saturation, increased aromatic hydrocarbon content, and greater fluidity. The heterogeneity of the components due to adsorption influences the physical properties and mineralization framework of tight oil reservoirs. These findings suggest that tight oil occurrence results from the coupling of microscopic occurrence and component heterogeneity in microscale and nanoscale pores.
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Li, Zhi Wen, Cheng Dong Liu, Xuan Qing Zhao, Jian Hui Lu und Guo Lin Guo. „The Mineral Characteristics and Occurrence of Gold in Nali Gold Deposit, Guangxi“. Advanced Materials Research 936 (Juni 2014): 2383–88. http://dx.doi.org/10.4028/www.scientific.net/amr.936.2383.
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Using the analysis techniques of polarizing optical microscope and electron probe, mineral composition, ore texture and structure and the occurrence of Au in the primary ore are studied. The research shows that the main ore minerals in the ore include realgar, pyrite and arsenopyrite etc. Sulfur-stibarsen is the main carrier of Au, and is the major associated mineral of realgar, surrounded mainly by realgar, and partly is the associated mineral of arsenopyrite. The existence of visible gold and microscopic gold in the ore of this mining area can be excluded, and the gold might exist mainly in the form of inclusion gold, which is the so-called “nanoAu”.
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Mills, Stuart J., und Andrew G. Christy. „Mineral extinction“. Mineralogical Magazine 83, Nr. 5 (20.09.2019): 621–25. http://dx.doi.org/10.1180/mgm.2019.60.
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Abstract‘Mineral evolution’ has attracted much attention in the last decade as a counterpart of the long-established biological concept, but is there a corresponding ‘mineral extinction’? We present new geochronological data from uranium-bearing secondary minerals and show that they are relatively recent, irrespective of the age of their primary uranium sources. The secondary species that make up much of the diversity of minerals appear to be ephemeral, and many may have vanished from the geological record without trace. Nevertheless, an ‘extinct’ mineral species can recur when physiochemical conditions are appropriate. This reversibility of ‘extinction’ highlights the limitations of the ‘evolution’ analogy. Mineral occurrence may be time-dependent but does not show the unique contingency between precursor and successor species that is characteristic of biological evolution.
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DRUMMOND, CARL N. „SOME CHARACTERISTICS AND CAUSES OF CHANGES IN THE RATE OF DISCOVERY OF NEW MINERALS SINCE 1800“. Earth Sciences History 43, Nr. 1 (08.05.2024): 118–39. http://dx.doi.org/10.17704/1944-6187-43.1.118.
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ABSTRACT Construction of a discovery curve for Earth's minerals illustrates an abrupt inflection in rates of discovery and acceptance of new species that occurred in the middle of the 20th century. Prior to that time new mineral discovery is found to have accelerated at a modest pace of 0.3 species / year2. Since 1950 the rate of acceptance has accelerated at an average of 1.04 species / year2 such that the first two decades of the 21st century have been characterized by the acceptance of over 100 new minerals per year. Despite this rapid acceleration of discovery, the relative distribution among the 10 mineral classes of the Nickel-Strunz classification system of minerals identified prior to and after 1950 are nearly identical. Variation in the rates of attestation of the divisions, families, and mineral groups show distinct differences in that the maximum rates of discovery of minerals populating higher taxonomic levels occurred prior to 1950 while the attestation curve of newly recognized groups closely follows that defined by the identification of mineral species. The application of any hierarchical classification system to the mineral species is somewhat arbitrary and subject to biases or inconsistencies associated with the systematics of classification. Therefore, the discovery of new minerals is also considered within the context of the mathematically defined crystallographic space group symmetries. The space group attestation curve has a shape similar to those exhibited by the higher taxonomic levels within the Nickel-Strunz system. However, not all space groups are represented by naturally occurring minerals. Minerals discovered before and after the inflection in rates of new mineral discovery illustrate significantly different patterns of paragenesis. Nearly all of the species have been associated with one or more of 57 distinct paragenetic modes. Minerals that have long been known tend to have a higher number of paragenetic modes than those more recently discovered such that the average number of paragenetic modes is shown to have decreased linearly from 1950 to 2022. Further, the earliest known occurrence of over 80% of the currently accepted mineral species has been tabulated by the International Mineralogical Association. For species discovered prior to the inflection of 1950 a linear distribution of oldest ages is observed indicating that these minerals have earliest ages of occurrence that are uniformly distributed across the interval 0 to 4700 Ma. Conversely, approximately 70% of the species identified since 1950 have oldest known occurrences of less than 600 Ma and the age distribution of these post-1950 minerals exhibit an exponential distribution suggesting increasing efforts in new mineral discovery in tectonically active settings. Despite the differences in the pre- and post-1950 oldest age distributions, both populations exhibit similar temporal excursions in rates of new mineral creation that likely reflect substantial changes in Earth system processes responsible for new mineral formation.
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Birdwell, Justin, Ronald C. Johnson und Michael E. Brownfield. „Distribution of mineral phases in the Eocene Green River Formation, Piceance Basin, Colorado—Implications for the evolution of Lake Uinta“. Mountain Geologist 56, Nr. 2 (01.05.2019): 73–141. http://dx.doi.org/10.31582/rmag.mg.56.2.73.
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The mineralogy of the Eocene Green River Formation in the Piceance Basin, Colorado, has been the subject of numerous studies since the 1920s. Most previous work has focused on the resource potential of these lacustrine mudrocks, which in addition to substantial oil shale potential (in-place resources of 353 billion barrels of synthetic crude oil for rocks yielding at least 25 gallons per ton, GPT), includes nahcolite, a currently utilized soda ash resource, and dawsonite, a potential alternative source of aluminum. Another reason to study the mineralogy in this system is that the geographic and stratigraphic distribution of various authigenic minerals may provide insights into the geochemistry and depositional environment of the long-lived Eocene Lake Uinta. In this study, legacy non-quantitative (presence/absence) X-ray diffraction (XRD) data recently published by the U.S. Geological Survey (USGS) for more than 9,000 samples collected from 30 coreholes in the Green River Formation, Piceance Basin were examined. These data were used to better define the stratigraphic and paleogeographic extent of a set of indicator minerals (illite, analcime, albite, dawsonite, and nahcolite) within the Piceance Basin lacustrine strata. This set of minerals was selected based on observations from previous work and variability in their occurrence and co-occurrence within the Piceance Basin. The USGS database has been used to (1) construct maps showing geographic variations in mineral occurrences for 14 stratigraphically defined rich and lean oil shale zones; (2) assess co-occurrences of indicator minerals; and (3) compare occurrence results with quantitative XRD datasets collected on Piceance Basin oil shales. Occurrences of many authigenic minerals (analcime, dawsonite, and nahcolite) varied in the lacustrine strata near and around the depocenter, but others, like quartz, dolomite, and feldspar (potassium + undifferentiated), were widely and consistently present (>90% of samples) across the basin. Shifts in the distribution of indicator mineral occurrences generally coincide with changes identified in previous lake history descriptions and indicate that the water chemistry of Lake Uinta varied significantly going from near-shore to the depocenter and through time.
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Zhu, Xiaojun, Jingong Cai, Yongshi Wang, Huimin Liu und Shoupeng Zhang. „Evolution of organic-mineral interactions and implications for organic carbon occurrence and transformation in shale“. GSA Bulletin 132, Nr. 3-4 (25.07.2019): 784–92. http://dx.doi.org/10.1130/b35223.1.
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Abstract Organic-mineral interactions are pervasive in sedimentary environments; however, the extent of these interactions is not constant and has a significant impact on organic carbon (OC) occurrence and transformation. To understand the evolution of organic-mineral interactions and the implications for OC occurrence and transformation in fine-grained sediments, several shale samples were selected and subjected to physical and chemical sequential treatments. The samples were subjected to pyrolysis, Fourier transform infrared spectrophotometry (FTIR), and adsorption measurements to determine the organic parameters and the mineral surface area (MSA) of the shale samples. The results show that the organic fractions derived from sequential treatments have varying pyrolysis and FTIR characteristics. The correlation between the total OC content and MSA is positive, but it is split according to organic fractions with different attributes. Correlations between the different organic fractions and MSA indicate that the organic matter in shale is mainly adsorbed on mineral surfaces, while a certain portion of organic matter occurs in the pores and is adsorbed on the organic-mineral aggregates, suggesting variable interactions between the organic fractions with different attributes and minerals. From the pyrolysis and FTIR analysis, the organic fractions of different occurrence sites vary in their OC proportion, proclivity to form organic functional groups, and hydrocarbon generation potential. With increasing burial depth, the MSA and hydrogen index as well as OC loading per unit MSA are reduced, and the OC proportions of organic fractions with different attributes have regular trends. These observations indicate that the extent of organic-mineral interactions that can stabilize organic matter gradually decreases, resulting in transformation of the tightly mineral-combined OC into free OC. Our work reveals the heterogeneity in organic matter occurrence and the effect of the evolution of the organic-mineral interactions on OC occurrence and transformation, which is significant in the global carbon cycle and in petroleum systems.
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Trichos, D., G. Alevizos, A. Stratakis, E. Petrakis und M. Galetakis. „Mineralogical investigation and mineral processing of iron ore from the Skines area (Chania – West Crete)“. Bulletin of the Geological Society of Greece 47, Nr. 4 (21.12.2016): 1652. http://dx.doi.org/10.12681/bgsg.11009.
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Several iron ore occurrences are placed in the island of Crete and especially in the prefectures of Chania and Rethymno (Western Crete), some of which have been occasionally exploited. The aim of the present study is the mineralogical examination and the investigation of mineral processing potential of an iron ore occurrence located in the area of Skines village near to the city of Chania. The investigated iron ore occurrence form lenses which are placed within the contact of the phyllitequartzite of Phyllite-Quarzite-Series (PQS) of Crete and the overlaid limestones. The major minerals of the iron ore are goethite, hematite and quartz, while the less common are muscovite, lepidocrocite, gibbsite, talc and pyrite. The ore microscopy exanimation indicated that an extended epigenetic ferruginisation process has taken place. In general, mineral processing by using heavy liquid and magnetic separation did not give satisfactory results, except for the size fraction -1+0,250 mm of the heavy liquid and the magnetic products of size ftactions -8+4 mm, -4+1 mm and -1+0,250 mm. Ore microscopy examination of the different size fractions indicated that the difficulties in mineral processing are closely related to the ore liberation.
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Luo, Guo Ping, Yan Ban, Yi Ci Wang, Wen Wu Yu und Qi Jiang. „The Occurrence of Special Components in Blast Furnace Slag of Baotou Iron and Steel Company“. Applied Mechanics and Materials 220-223 (November 2012): 117–22. http://dx.doi.org/10.4028/www.scientific.net/amm.220-223.117.
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The mineral composition of the solidified blast furnace slag and the occurrence of special components CaF2, K2O, Na2O, RexOy and ThO2 were researched by optical microscope analysis, X-ray diffraction analysis and scanning electron microscopy and energy spectrum analysis. The results showed that the major minerals in solidified furnace slag are akermanite and gehlenite; the special component CaF2 is not hosted in the cuspidine (3CaO•2SiO2•CaF2), but in the magnesium and aluminum silicate mineral; the special components K2O，Na2O is hosted in akermanite, magnesium and aluminum silicate mineral and perovskite; the element thorium cannot form an independent mineral, but coexist with the rare earth element Ce in the perovskite. The results will lay a foundation for further study on the influence of these special components on the crystallization behavior of glass-ceramics.
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Petrov, Petko, Tsveta Stanimirova und Svetla Stariradeva. „First occurrence of the mineral osakaite Zn4(OH)6(SO4)•5H2O for Bulgaria“. Review of the Bulgarian Geological Society 83, Nr. 3 (Dezember 2022): 35–38. http://dx.doi.org/10.52215/rev.bgs.2022.83.3.35.
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Osakaite, a new mineral for Bulgaria, was discovered in stalactites from the Gyudyurska mine, South Petrovitsa deposit, South Rhodope. The chemical composition determines isomorphous inclusion of Cu2+ and composition (Zn3Cu)(OH)6(SO4)•5H2O. The mineral is a product of the interaction of mine waters passing through Zn and Cu-sulfide ores. During prolonged storage in atmospheric conditions, part of the osakaite crystals were dehydrated to the formation of the minerals namuwite Zn3Cu(OH)6(SO4)•4H2O and lahnsteinite Zn3Cu(OH)6(SO4)•3H2O.
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Sodov, Ariunbileg, Olga Gaskova, Altansukh Gankhuyag, Dagva-Ochir Lkhagvasuren, Otgonbaatar Dorjsuren, Oyunchimeg Tumen-Ulzii und Battushig Altanbaatar. „New orogenic type gold occurrences in the Uyanga ore knot (Central Mongolia)“. Mongolian Geoscientist, Nr. 47 (31.12.2018): 22–36. http://dx.doi.org/10.5564/mgs.v0i47.1062.
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The Uyanga ore knot district of the Khangay metallogenic zone are hosted by the lower-middle Devonian volcanogenic-sedimentary Erdenetsogt formation. About 40 samples were collected from the host rocks, veins and quartz veins in the Uyanga ore knot district in 2016. The new Burgetei, Ult and Senjit gold occurrences were studied. The quartz-sulfide, gold-arsenic and gold-antimony-mercury mineralization are determined in the berecitization, silicification, limonitization and glauconization altered metasomatic zones within the Uyanga ore knot districts. The rocks of the Erdenetsogt formation have an irregular gold content: 0.96 g/t Au is determined in quartz vein taken from trench of the Burgetei occurrence (BG-7/16), Au content is highest up to 3.5 g/t in the quartzite-jasper (Ult-7/16 and Ult-9/16) cut by quartz veins in the Ult occurrence. The Senjit occurrence represents Au-Hg-Sb epizonal level of orogenic gold deposits structure with highest Hg content up to 851 ppm. This year no sulfide minerals were found in the siltstone of this occurrence. The Au content of arsenical pyrite of the Burgetei and Ult is below the detection limit by electron microprobe analysis. The Au content of arsenopyrite of the Ult occurrence is highest (up to 238 ppm). Therefore, the ore-mineral assemblages in the gold occurrences reflect the differences between the three explored sites, formed in the course of fluid evolution during the fluid-rock interaction. Variable concentrations of indicative elements (As, Te, Sb, Hg) and their ratios confirm this fact. The geodynamic position, the type of the hydrothermal alteration of both igneous and sedimentary rocks, textures and mineral assemblages, the mineralization sequences are consistent with orogenic classification for the Burgetei, Ult and Senjit gold occurrences.
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Li, La Mei, Yu Ling Xie und Ying Xu Li. „Study on Metallurgical Mineralogy in Nongruri Gold Deposit, Tibet“. Advanced Materials Research 962-965 (Juni 2014): 789–92. http://dx.doi.org/10.4028/www.scientific.net/amr.962-965.789.
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The Nongruri gold deposit is located in Mozhugongka, Tibet.There are two occurrence states of gold in Nongruri deposit, native gold and lattice gold. Fine grained native gold is hosted in clay minerals, and lattice gold just occupies little part. Gold particle size ranges from less than 0.001mm to 0.034mm, mainly in > 0.02mm, about 52.13wt% of total mount. According to the composition of mineral, occurrence state of gold and particle size measurement results of gold and gold-bearing mineral, it is a kind of fine-grained uneven refractory ore, and the recommended grind size should be smaller than-200 mesh.
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Ferry, John M. „Patterns of mineral occurrence in metamorphic rocks“. American Mineralogist 85, Nr. 11-12 (November 2000): 1573–88. http://dx.doi.org/10.2138/am-2000-11-1201.
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Łaciak, Dagmara. „Creating the so-called graphite-coated pottery of the Late Bronze and Early Iron Ages“. Archeologické rozhledy 75, Nr. 1 (25.09.2023): 7–23. http://dx.doi.org/10.35686/ar.2023.2.
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Over the centuries, various minerals were used in pottery production; for some societies, graphite played a unique role. Certain areas lack local sources of this mineral but simultaneously reveal a great occurrence of ‘graphite-coated’ pottery. Still, it is commonly believed that the surface of these vessels was coated with graphite. The aim of the article is to examine whether the surface visually characterised as ‘graphited’ (suggesting the use of graphite) could be achieved without the application of the mineral and what the technological process of manufacturing might have looked like. Macroscopical and archaeometry recognition features of ‘graphite-coated’ pottery and mineral graphite were indicated. A series of experiments were performed to achieve a lustrous, silver surface without applying mineral graphite. The firing process was conducted in two types of kilns reconstructed according to archaeological sources from the territory of Poland dated to the Late Bronze and Early Iron Ages. The reproduced pottery shows surfaces very similar to their prehistorical counterparts. The significant occurrence of this type of pottery indicates its production could also be conducted in areas lacking mineral graphite.
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THOMAZ, MARIA C., PEDRO H. WATANABE, LEONARDO A. F. PASCOAL, MURILO M. ASSIS, URBANO S. RUIZ, ALESSANDRO B. AMORIM, SUSANA Z. SILVA, VIVIAN V. ALMEIDA, GABRIEL M. P. MELO und RIZAL A. ROBLES-HUAYNATE. „Inorganic and organic trace mineral supplementation in weanling pig diets“. Anais da Academia Brasileira de Ciências 87, Nr. 2 (28.04.2015): 1071–81. http://dx.doi.org/10.1590/0001-3765201520140154.
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A study was conducted to evaluate the effects of dietary inorganic and organic trace minerals in two levels of supplementation regarding performance, diarrhea occurrence, hematological parameters, fecal mineral excretion and mineral retention in metacarpals and liver of weanling pigs. Seventy piglets weaned at 21 days of age with an average initial body weight of 6.70 ± 0.38 kg were allotted in five treatments: control diet (no added trace mineral premix); 50% ITMP (control diet with inorganic trace mineral premix supplying only 50% of trace mineral requirements); 50% OTMP (control diet with organic trace mineral premix supplying only 50% of trace mineral requirements); 100% ITMP (control diet with inorganic trace mineral premix supplying 100% of trace mineral requirements); and 100% OTMP (control diet with organic trace mineral premix supplying 100% of trace mineral requirements). Feed intake and daily weight gain were not affected by treatments, however, piglets supplemented by trace minerals presented better gain:feed ratio. No differences were observed at calcium, phosphorus, potassium, magnesium, sodium and sulfur excreted in feces per kilogram of feed intake. Treatments did not affect calcium, phosphorus, magnesium, sulfur and iron content in metacarpals. Trace mineral supplementation, regardless of level and source, improved the performance of piglets.
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Alikin, O. V., A. V. Chumakov und V. N. Rudashevsky. „Mineralogical and Petrographic Features and Mineral Formation Sequence of Gold-Antimony Ores from Udereyskoe Deposit (Krasnoyarsk Region)“. Вестник Пермского университета. Геология 22, Nr. 1 (2023): 51–79. http://dx.doi.org/10.17072/psu.geol.22.1.51.
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The article presents results of petrographic and mineralogical studies of gold-antimony ores of the Udereyskoe deposit and their concentration products. The main mineral associations of ores are characterized, mineral forms of occurrence are revealed, and distribution of Au, Pd, Ag is estimated. The paragenetic scheme of mineral formation sequence was clarified and supplemented. The important mineral forms of gold occurrence are goldbearing arsenopyrite and native gold (Au,Ag), as well as rare aurostibite AuSb2 and intermetallides such as antimony gold (Au,Sb), and palladium gold (Au,Pd). The revealed diversity of forms of noble metals and analysis of their relationships with associating sulfides and nonmetallic minerals indicate at least two contrasting early and late stages of ore genesis. Early quartz-pyrite and late pyrite, which are two stages of mineralization, are determened within the early stage. Three consecutive stages of mineralization are established in the late stage: quartz-stibnite, pyrite-stibnite-quartz, and pyrite-arsenopyrite-stibnite.
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Hendrickx, Marc. „Fibrous Tremolite in Central New South Wales, Australia“. Environmental and Engineering Geoscience 26, Nr. 1 (20.02.2020): 73–77. http://dx.doi.org/10.2113/eeg-2273.
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ABSTRACT Tremolite schists in Ordovician meta-volcanic units in central New South Wales (NSW) consist of fine fibrous tremolite-actinolite. They host tremolite asbestos occurrences, and small quantities of asbestos were mined from narrow vein deposits in central NSW during the last century. When pulverized, the tremolite schist releases mineral fragments that fall into the classification range for countable mineral fibers and may be classed as asbestos despite not having an asbestiform habit. The ambiguity in classification of this type of natural material raises significant health and safety, legal, and environmental issues that require clarification. While the health effects of amphibole asbestos fibers are well known, the consequences of exposure to non-asbestiform, fibrous varieties is not well studied. This group of elongated mineral particles deserves more attention due to their widespread occurrence in metamorphic rocks in Australia. Toxicological studies are needed to assess the health risks associated with disturbance of these minerals during mining, civil construction, forestry, and farming practices.
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Kempe, U., J. Götze, S. Dandar und D. Habermann. „Magmatic and metasomatic processes during formation of the Nb-Zr-REE deposits Khaldzan Buregte and Tsakhir (Mongolian Altai): Indications from a combined CL-SEM Study“. Mineralogical Magazine 63, Nr. 2 (April 1999): 165–77. http://dx.doi.org/10.1180/002646199548402.
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AbstractCathodoluminescence (CL) imaging and spectroscopy, as well as backscattered electron imaging, were used to assign the occurrence of several mineral phases and rock structures in altered nordmarkites and calcite-bearing granites from the Nb-Zr-REE deposits from Khaldzan Buregte and Tsakhir (Mongolian Altai) to three events: (1) intrusion of barren nordmarkites; (2) intrusion of small bodies of calcite-bearing granites with metasomatic alteration of the wall-rocks; and (3) alteration by F-rich fluids.Unusual red and yellow CL caused by Fe3+ and Mn2+ emission centres were detected in microcline and albite. Fe3+ centres were also established (along with others) in quartz, zircon, and possibly in fluorite.Magmatic and metasomatic rock structures and internal structures of the minerals coexist in the samples. The primary magmatic features were in part preserved during alteration. In contrast, the internal and the centre structures may be changed during alteration even in non-replaced mineral phases. Euhedral minerals may be formed by secondary processes as shown for lath-shaped albite. The occurrence of pseudomorphs, the inheritance of elements during replacement, and the mechanical effects of secondary minerals on earlier mineral phases during metasomatic growth are proposed as criteria for the reconstruction of the mineral succession in altered rocks. Snowball structures may be formed as a result of metasomatic alteration rather than as a magmatic intergrowth.
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Novakov, Roman, Valentina Kungurova und Svetlana Moskaleva. „Formation conditions of noble metal mineralization in sulfide cobalt-copper-nickel ores of Kamchatka (on the example of Annabergitovaya Schel ore occurrence)“. Journal of Mining Institute 248 (25.05.2021): 209–22. http://dx.doi.org/10.31897/pmi.2021.2.5.
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The authors present research results, the purpose of which is to study the specifics of noble metal mineralization and its genesis in sulfide cobalt-copper-nickel ores of the Kamchatka nickel-bearing province. The paper is dedicated to one of its many ore occurrences called Annabergitovaya Schel (Annabergite Gap). The material composition of platinoid, silver, gold, bismuth and tellurium minerals, as well as sulfarsenides in the ores of this occurrence was investigated. Based on the data of mineral formation sequence and the use of geosensors, conclusions were drawn regarding the genesis of noble metal mineralization.
Formation of platinoid minerals, silver and gold at the Annabergitovaya Schel ore occurrence is mainly associated with the epigenetic effect of post-ore granitoids on ore-bearing intrusion rocks of the Dukuk complex of the cortlandite-norite formation and on syngenetic ores. An early association of noble metal minerals is represented by sperrylite, irarsite, and rare unnamed phases of Pt + Ir + Te. Irarsite and Pt + Ir + Te phases were formed at the contact-metasomatic stage. Sperrylite can be assumed to be of magmatic origin. Silver sulfides and tellurides, silver and palladium bismuth tellurides, and native gold were formed at the late, hydrothermal-metasomatic, stage. The occurrence conditions of mineral parageneses, associated with noble metal mineralization, correspond to the formation of shallow-depth metasomatic rocks (5 km). Sub-developed quartz-feldspar metasomatites, associated with the formation of early platinoid arsenides and sulfarsenides, are in equilibrium with circumneutral solutions (pH of 4.5-6.5) at temperatures of 350-600 °C. Late hydrothermal association with Pd, Ag and Au minerals is close to propylites and was formed at pH values of 4.5-6.5 and temperature of 150-350 °C.
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Wang, Baohua, Mingbo Zhang, Yongyu Gong, Shiping Huang, Shengtao Qiu und Rong Zhu. „Effects of cooling methods on the occurrence of sulfur in the low-titanium slag“. Metallurgical Research & Technology 115, Nr. 2 (2018): 208. http://dx.doi.org/10.1051/metal/2017077.
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The distribution of sulfur existence in the mineral phase and occurrence in the low-titanium slag with different cooling methods (water cooling, air cooling, crucible cooling, and furnace cooling) were studied by XRD, EPMA and XPS. The results show that with the cooling rate decrease, the distribution of S changes from clustering dots to large sheet or surface, and the occurrence of S in the mineral phase transfers gradually from the vitreous, perovskite, merwinite and the intertwined phase of some mineral phases to the gehlenite. During the transfer, the velocity decreases with the increasing of the cooling rate. The S in the water cooling slag only exists in the form of SO32−and SO42−, while the occurrences of S in the air cooling slag, crucible cooling slag, and furnace cooling slag are S2−, SO32−and SO42−.
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DALTRY, Vaughan D. C., und Oleg von KNORRING. „Type-mineralogy of Rwanda with particular reference to the Buranga pegmatite“. Geologica Belgica 1, Nr. 1-4 (31.01.1998): 9–15. http://dx.doi.org/10.20341/gb.2014.002.
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The type-mineralogy of Rwanda is reviewed. Six type-mineral names are presented, comprising four approved valid species and two non-valid phases. An unnamed mineral is also given. The four approved species are described from two type localities: Buranga and Lutsiro. One of these minerals remains unique to the type occurrence. All but one of the described type-phases occur in the Buranga pegmatite, which is host to over hundred other valid species. More than half the recorded minerals from Buranga are phosphates of which two compositional groups are recognised: Al-dominant and Fe-Mn-dominant phases.
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Liu, Taotao, Wenlei Song, Jindrich Kynicky, Jinkun Yang, Qian Chen und Haiyan Tang. „Automated Quantitative Characterization REE Ore Mineralogy from the Giant Bayan Obo Deposit, Inner Mongolia, China“. Minerals 12, Nr. 4 (30.03.2022): 426. http://dx.doi.org/10.3390/min12040426.
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Rare earth elements (REEs) are considered critical elements in modern society due to their irreplaceable role in new innovative and energy technologies. The giant carbonatite-related Bayan Obo deposit contributes most REE resources in the world’s market, while its origin is still unclear because of the complicated and diverse REE ore mineralogy and texture. Thescanning electron mircroscopy SEM)-based automated mineralogy allows for the numeric assessment of rocks and ores’ compositional and textural properties. Here, we use TIMA (TESCAN Integrated Mineral Analyzer) to quantitatively characterize REE ore mineralogy from the deep drill core within the H8 unit (“dolomite marble”) to better understand the deposit. The mineral composition, occurrence, and Ce elemental deportment of the borehole ores at different depths (i.e., 1107 m, 1246 m, 1406 m, 1546 m, and 1682 m) were obtained. The results show that the main types of ores in the investigated samples can be divided into banded REE-Fe ores, banded REE ores, disseminated REE-Fe ores, and veined REE ores. REE and gangue minerals vary significantly in abundance and occurrence. Monazite-(Ce) and bastnäsite-(Ce) are the primary REE host minerals, and both contribute the most to the REE budget. Other REE minerals, such as parisite-(Ce)/synchysite-(Ce), cerite-(Ce), huanghoite-(Ce)/cebaite-(Ce), and aeschynite-(Ce), are significant contributors. The gangue minerals generally include fluorite, barite, magnetite, pyrite, quartz, magnesio-arfvedsonite, and minerals of the biotite and apatite groups, among others. Combined with the newly published mineral-scale chronological and isotopic geochemical analyses, it is reasonable to conclude that the later hydrothermal fluids remobilized and redistributed the original Mesoproterozoic carbonatitic REE minerals and formed a high variable ore mineral assemblage. Furthermore, it is demonstrated that the mineralogical study using TIMA can provide accurate and reliable mineralogy data for the comprehensive interpretation of the complex REE ores, and extend our understanding of the deposit.
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Sikorska-Maykowska, Małgorzata, Iwona Walentek und Kamila Andrzejewska-Kubrak. „Criteria for Geo-Environmental Evaluation of Prospective Areas of Mineral Deposit Occurrence“. Gospodarka Surowcami Mineralnymi 33, Nr. 2 (27.06.2017): 81–95. http://dx.doi.org/10.1515/gospo-2017-0012.
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Abstract In this work, we present the problem of geo-environmental assessment of prospective areas of mineral deposits occurrence in Poland. T he issue is discussed mainly based on data from the database of Geo-environmental map of Poland, scale 1:50 000 (MGśP II). While for proven deposits a classification based on environmental conditions has been used for many years, for prospective areas of mineral occurrence such an assessment is not conducted. Taking into consideration not only protection of the natural environment, but also protection of mineral resources in Poland, it is necessary to review the approach to areas with prospective mineral resources from the point of view of their role in land use planning. Such prospective areas have - depending on the type of mineral in question, how large an area has been prospected, its geological structure - highly diverse surface area, from just a few to thousands of hectares. T his means the approach to environmental assessments of prospective areas of mineral occurrence must be different from that for already proven locations of mineral resources. The article presents quantitative characteristics of prospective areas of mineral occurrence presented on the aforementioned MGśP II map for Poland. We propose herein criteria for environmental evaluation of such prospective areas, differentiating them mainly depending on the type of mineral, manner of exploitation, surface area and land use legal forms, as well as possibility of future reclamation.
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Wu, Bin, Han-Jie Wen, Christophe Bonnetti, Ru-Cheng Wang, Jin-Hui Yang und Fu-Yuan Wu. „Rinkite-(Ce) in the nepheline syenite pegmatite from the Saima alkaline complex, northeastern China: Its occurrence, alteration, and implications for REE mineralization“. Canadian Mineralogist 57, Nr. 6 (30.11.2019): 903–24. http://dx.doi.org/10.3749/canmin.1900042.
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Abstract The nepheline syenite pegmatite in the Saima alkaline complex in northeastern China is characterized by REE mineralization, mainly rinkite-(Ce) and associated alteration minerals. As the most abundant REE-bearing mineral in the pegmatite, rinkite-(Ce) closely coexists with microcline, nepheline, natrolite, and calcite. Some rinkite-(Ce) grains show compositional sector-zonation, in which the inner core displays relatively high Ti, Ca, and Sr concentrations, but low Zr, REE, and Na contents. Primary rinkite-(Ce) has undergone multiple episodes of fluid interactions, and accordingly, from weak to strong, three different mineral assemblages of hydrothermal alteration can be summarized: (1) rinkite-(Ce) + secondary natrolite ± K-feldspar ± minor fluorbritholite-(Ce); (2) rinkite-(Ce) relics + secondary natrolite + K-feldspar + fluorbritholite-(Ce) + unidentified Ca-Ti silicate mineral + fluorite and calcite; and (3) pseudomorphs after rinkite-(Ce). The pseudomorphs can be divided into two groups characterized by distinct mineral associations: (1) Ca-bearing strontianite + fluorbritholite-(Ce) + natrolite + fluorite + calcite coexisting with silicate minerals; and (2) calcite + fluorite + fluorbritholite-(Ce) + rinkite-(Ce) relics ± Ca-bearing strontianite ± ancylite-(Ce) associated with a calcite matrix. These alteration mineral assemblages are evidence of magmatic-derived alkali metasomatism due to an alkali-CO2-F-rich fluid and Ca-metasomatism due to a different, externally derived Sr- and Ca-rich fluid. The metasomatic events acted as the potential driving force for the rinkite-(Ce) dissolution and pseudomorph-forming process. The high concentration of rinkite-(Ce) in the nepheline syenite pegmatite results from the fractional crystallization of the Saima CO2-rich alkaline silicate magma, and the successive alterations of rinkite-(Ce) attest to the important role played by hydrothermal fluids in controlling the remobilization of REE and the crystallization of secondary rare earth minerals.
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Turci, Francesco, Jasmine Rita Petriglieri, Luca Barale, Elena Gazzano, Elisabetta Aldieri, Maura Tomatis, Paolo Ballirano, Fabrizio Piana, Antonella Campopiano und Alessandro Pacella. „154 Toward a General Approach to Risk Assessment of Naturally Occurring Asbestos and Asbestos-Like Minerals: the case of Fibrous Antigorite“. Annals of Work Exposures and Health 67, Supplement_1 (01.05.2023): i75—i76. http://dx.doi.org/10.1093/annweh/wxac087.182.
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Abstract The natural occurrence of asbestos and asbestos-like minerals (NOA) poses a risk to the environment and human health, notably when natural processes and anthropic activities promote fibre dispersion. Hundreds of potentially hazardous elongated mineral particles (EMPs, NIOSH 2011 definition) exist, and their toxicological profile is often unknown. We aim here to define a general approach, from field analysis to nano-structural investigation, to assess whether a fibrous mineral occurring in a specific site could pose a risk to human health. To evaluate the hazard associated with NOA, a multi-scale and multi-analytical integrated approach was adopted. Specifically, the geological factors that control the occurrence and distribution of NOA on site, and the mechanisms of formation and liberation of airborne fibres were investigated. In parallel, we explored the key bulk and surface properties of several natural mineral fibres and defined crystallographic, chemical, and morphological aspects that should be considered during hazard assessment. Also, the effect of standardized mechanical stress was used to simulate variation on morphometric parameters of investigated minerals and allowed us to quantitatively evaluate the potency to generate inhalable fibres. This property was connected with the mineral characteristic and the rock fabric. Isolated fibre specimens were used to assess solubility in simulated body fluids, surface reactivity, and toxicological endpoints in vitro and in vivo. Taken together, these findings allowed us to build a multidimensional description of the hazard parameters of a mineral fibre and paved the way for a science-based risk assessment in an unexplored NOA site.
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Makvandi, Sheida, Philippe Pagé, Jonathan Tremblay und Réjean Girard. „Exploration for Platinum-Group Minerals in Till: A New Approach to the Recovery, Counting, Mineral Identification and Chemical Characterization“. Minerals 11, Nr. 3 (04.03.2021): 264. http://dx.doi.org/10.3390/min11030264.
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The discovery of new mineral deposits contributes to the sustainable mineral industrial development, which is essential to satisfy global resource demands. The exploration for new mineral resources is challenging in Canada since its vast lands are mostly covered by a thick layer of Quaternary sediments that obscure bedrock geology. In the course of the recent decades, indicator minerals recovered from till heavy mineral concentrates have been effectively used to prospect for a broad range of mineral deposits including diamond, gold, and base metals. However, these methods traditionally focus on (visual) investigation of the 0.25–2.0 mm grain-size fraction of unconsolidated sediments, whilst our observations emphasize on higher abundance, or sometimes unique occurrence of precious metal (Au, Ag, and platinum-group elements) minerals in the finer-grained fractions (<0.25 mm). This study aims to present the advantages of applying a mineral detection routine initially developed for gold grains counting and characterization, to platinum-group minerals in <50 µm till heavy mineral concentrates. This technique, which uses an automated scanning electron microscopy (SEM) equipped with an energy dispersive spectrometer, can provide quantitative mineralogical and semi-quantitative chemical data of heavy minerals of interest, simultaneously. This work presents the mineralogical and chemical characteristics, the grain size distribution, and the surface textures of 2664 discrete platinum-group mineral grains recovered from the processing of 5194 glacial sediment samples collected from different zones in the Canadian Shield (mostly Quebec and Ontario provinces). Fifty-eight different platinum-group mineral species have been identified to date, among which sperrylite (PtAs2) is by far the most abundant (n = 1488; 55.86%). Textural and mineral-chemical data suggest that detrital platinum-group minerals in the studied samples have been derived, at least in part, from Au-rich ore systems.
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Akon, Eunuse. „Mineralogy, geochemistry and economic potentialities of heavy mineral sand resources of Bangladesh“. Journal of Nepal Geological Society 59 (24.07.2019): 1–8. http://dx.doi.org/10.3126/jngs.v59i0.24981.
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Heavy mineral sand deposits are the important mineral resources of Bangladesh. Systematic mineral exploration activities carried out in the south eastern coastal belt of Bangladesh were successful to discover seventeen heavy mineral sand (HMS) deposits in the coastal beach and off-shore islands. Mineralogy, geochemistry and mineral processing characteristics of the heavy mineral sands and their economic potentialities are presented in the present paper. On an average, HMS deposits contain 23% total heavy minerals. In heavy fraction, average weight percentage of the economic minerals is: zircon 4.20%, rutile 2.04%, ilmenite 26.03%, garnet 6.45%, kyanite 3.92%, leucoxene 2.30%, magnetite 1.87% and monazite 0.31%; and the average weight percentage of other non-economic heavy minerals is 53.88%. Heavy mineral sand deposits altogether contain 1.76 million tons of economically important heavy minerals which are: limonite (1,025,000 tonnes), garnet (223,000 tons), zircon (158,000 tonnes), leucoxene (97,000 tons), kyanite (91,000 tons), rutile (70,000 tons), magnetite (81,000 tones) and monazite (17,000 tonnes). Occurrence of large amount of economic heavy minerals in the sand bars of Brahmaputra-Jamuna River has been reported by some recent studies. On an average, total heavy mineral percentage of the Brahmaputra-Jamuna sand bars is around 8.92%. Mineral sand processing on the bulk samples has been carried out at the pilot plant comprising gravity, magnetic and electrostatic separators to characterize the separation characteristics of individual economic heavy minerals. Geochemical studies on the separated heavy minerals show that TiO2 in rutile is around 90% and ZrO2 in zircon is around 65%, which are quite satisfactory in respect of commercial grade. Ilmenite contains low level of titanium dioxide (TiO2-43%) and higher level of chromium, manganese and iron. Beneficiation and upgrading of limonite will be required to make it a market able commodity. Valuable minerals present in the heavy mineral sand deposits of Bangladesh need to be mined sustainably and utilized for the benefit of the country.
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Armour-Brown, A., und B. Wallin. „Ketilidian uranium mineral occurrences in South Greenland“. Rapport Grønlands Geologiske Undersøgelse 125 (31.12.1985): 66–74. http://dx.doi.org/10.34194/rapggu.v125.7895.
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The Sydex project is financed by the Ministry of Energy's Research Programme 1984 in order to evaluate the uranium mineral occurrences found during the earlier reconnaissance project, Syduran. The main objectives of the field season were: (1) to map and sample in detail the uranium occurrence at Igdlorssuit (fig. 20) in the Migmatite Complex which was found in 1982 (Armour-Brown et al., 1984), so as to evaluate its economic potential and place it in its geological setting, (2) to locate the source of a high gamma-spectrometer anomaly on the nunatak north of Nordre Sermilik in the Granite Zone, and to map the surrounding geology.
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Susilawati, Rita. „NON-MINERAL INORGANIC CONSTITUENTS OF BUKIT ASAM COAL NATURE AND MODE OF OCCURRENCE“. Buletin Sumber Daya Geologi 10, Nr. 2 (08.08.2015): 14–30. http://dx.doi.org/10.47599/bsdg.v10i2.139.
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The nature and mode of occurrence of the non-mineral inorganic fractions in coal from the Bukit Asam coalfield South Sumatra Basin Indonesia were analysed using a combination of selective leaching, low temperature ashing, XRD, XRF and electron micropobe techniques. Geologically the rank of coal at Bukit Asam was influenced by igneous intrusion. Fourteen coal samples were used in this study. Samples are chosen to represent different rank levels as well as seam horizons. The inorganic elements, in the form of dissolved salts, exchangeable ions and organometallic complexes, although present in small proportions, contribute significantly to the mineral matter components of Bukit Asam low rank coal. Electron microprobe analysis showed small but significant concentrations of inorganic elements (Al, Ca and Fe) occurring in the individual macerals in two sub bituminous and twosemi anthracite samples. There is a tendency for some of the elements, particularly Ca and Al to be lost from the organic matter with rank advance. The concentrations of elements indicated by the microprobe are relatively in good agreement with the levels of element mobility indicated by selective leaching of the same whole-coal samples. The results of this study also suggest that non-mineral inorganic was likely act as a precursor for the reactions resulting in the formation of new minerals in the high rank coals at Bukit Asam.
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M, Abhijit, und Suresh Kumar B. V. „Synthesis and Characterization of Calcium Zeolite-Cowlesite.“ Journal of University of Shanghai for Science and Technology 23, Nr. 05 (29.05.2021): 787–90. http://dx.doi.org/10.51201/jusst/21/05216.
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Cowlesite is a Calcium Aluminum silicate CaAl2Si3O106H2O which formed under the hydrothermal conditions of low temperature (1800C) and pressure (1.013250bar). Cowlesite minerals are known for their peculiar occurrence. Synthesis of Cowlesite mineral was carried by suitable stoichiometric composition. Hydrothermal synthesized Cowlesite mineral was characterized by XRD, SEM, and EDAX. It crystallized in the orthorhombic system and a lattice parameter a=23.22Å, b=30.58Å, c=25.01Å, Volume of Unit cell=17758.79Å3, α=β=γ=900. EDAX results show the elemental concentration of raw material which was used.
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Tomašić, Nenad, Radek Škoda, Vladimir Bermanec und Marin Šoufek. „Crystal chemistry and microfeatures of gadolinite imprinted by pegmatite formation and alteration evolution“. American Mineralogist 105, Nr. 11 (01.11.2020): 1647–55. http://dx.doi.org/10.2138/am-2020-7355.
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Abstract Gadolinite [REE2Fe2+Be2Si2O10] is a common mineral in certain types of rare element and rare earth element (REL-REE) pegmatites. Changes in pegmatite environment during and after gadolinite formation may be devised by studying its crystal-chemical properties and a thorough observation of microfeatures in the mineral matrix. Post-crystallization processes in pegmatite might trigger alteration mechanisms in gadolinite like in other REE-rich pegmatite minerals, whereby various late-magmatic or metasomatic events may affect mineral chemistry. Three gadolinite samples originating from various pegmatite occurrences in southern Norway offer an excellent opportunity in studying post-crystallization evolution of the pegmatites; by determining their crystallographic, chemical, and micro-textural features, imprints of the related processes in the pegmatites have been characterized in this study. Relevant mineral information was collected in recrystallization experiments of fully or slightly metamictized gadolinite samples and subsequent XRD analyses. Micro-Raman spectroscopy, electron microprobe analysis (EMPA), and scanning electron microscope–backscattered electron–energy-dispersive X-ray spectroscopy (SEM-BSE-EDS) analyses were employed to retrieve micro-chemical properties and related micro-textural features of the mineral matrix. With a reference to the gadolinite supergroup, a general alteration path can be envisaged outlining the pegmatite evolution and suggesting the occurrence of the secondary REE mineral phases: altered gadolinite domains prove Ca enrichment with a tendency toward the hingganite composition, while a slight fluorine increase and sporadic secondary fluorite occurrence imply a significant role of fluorine as a complexing agent in the dissolution-reprecipitation mechanism of metasomatic alteration in the mineral. Micro-Raman spectra show improved vibration statistics for the altered gadolinite domains, which could be linked to the substitution of rare earth elements (REE) by Ca and a possible increase of structural ordering within the gadolinite structure, being at the same time an indication of structural healing of metamictized domains by metasomatic processes. A study of microfeatures in the complex silicates like gadolinite proves to be an excellent tool to trace post-crystallization processes in a pegmatitic environment. With a slight redistribution of radionuclides during an alteration in gadolinite, a moderate precaution has to be taken when selecting gadolinite for U-Th-Pb dating.
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Billon, Sophie, Patricia Patrier, Daniel Beaufort, Paul Sardini und Aurélia Wattinne-Morice. „Occurrence of tosudite in the Guezouman, Tarat and Tchirezrine 2 formations, hosts of uranium deposits in Niger (Tim Mersoï basin)“. Clay Minerals 51, Nr. 4 (September 2016): 635–51. http://dx.doi.org/10.1180/claymin.2016.051.4.07.
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AbstractTosudite, a regularly interstratified chlorite-smectite, crystallizes as an alteration mineral of several preexisting Al-bearing silicates (feldspars, kaolin minerals, chlorites) present in arkosic sandstones hosted in uranium deposits in Niger. X-ray diffraction patterns show a sharp superstructure at 29–29.6 Å for an air-dried state and a peak at 30.8–31.6 Å following ethylene glycol solvation. The 060 reflection at 1.507–1.509 Å indicates an overall dioctahedral character, and the very low coefficient of variation of the d00l reflections for the solvated mineral (0.03–0.13) permits validation of the regular interstratification justifying its identification as tosudite. Microprobe analysis allowed specification of the component layers of this mixed-layer mineral. The chlorite is a di-trioctahedral type analogous to sudoite (Si3Al4Mg2(OH)8), and the smectite component is a low-charge montmorillonite type Tosudite is characterized by large Al2O3 and MgO contents and small Fe content; its composition corresponds approximately to the formula where octahedral occupancy is ∼7. Scanning electron microscope (SEM) observations show that tosudite is closely associated with some uranium minerals: tosudite crystallization occurred during a late alteration event which post-dates burial diagenesis and during which uranium was remobilized by Mg-rich oxidizing fluids.
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Thorning, Leif, Lisbeth Aa Christensen, Bo Møller Nielsen, Frands Schjøth und Henrik Stendal. „On-line presentation of mineral occurrences in Greenland“. Geological Survey of Denmark and Greenland (GEUS) Bulletin 7 (29.07.2005): 57–60. http://dx.doi.org/10.34194/geusb.v7.4839.
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The Geological Survey of Denmark and Greenland (GEUS) and the Bureau of Minerals and Petroleum (BMP, under the Government of Greenland) have co-operated on the international promotion of the mineral resources of Greenland for more than ten years. The Government of Greenland follows a strategy aimed at the development of a mining and petroleum sector in Greenland capable of yielding a significant proportion of the national income. To reach this goal it is necessary to attract international investment. In respect of mineral exploration, many parts of Greenland can still be considered virgin territory and it is therefore vital that all data relevant for the identification of possible exploration targets are available to the international mining industry. GEUS has produced many compilations of geoscience data for that purpose in traditional reports, on CD-ROMs and in scientific journals. In 2004, a new source of geoscience information was developed based on an interactive GIS facility on the Internet, and mineral exploration data and information from a region in central West Greenland are now accessible at the Greenland Mineral Occurrence Map (GMOM) website at GEUS (Fig. 1; www.geus.dk/gmom). Technically, this new facility will be maintained and developed in accordance with general principles for Internet services adopted by GEUS (e.g. Tulstrup 2004). New information from other regions of Greenland will gradually be added.
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Gomes, Celso de Barros, Rogério Guitarrari Azzone, Gaston Eduardo Enrich Rojas, Vincenza Guarino und Excelso Ruberti. „Agpaitic Alkaline Rocks in Southern Brazilian Platform: A Review“. Minerals 11, Nr. 9 (27.08.2021): 934. http://dx.doi.org/10.3390/min11090934.
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General information is presented on ten agpaitic occurrences located in southern Brazil and at the border between Brazil and Paraguay. All the Brazilian agpaitic rocks are Late Cretaceous in age, whereas the Paraguayan ones are older than Early Triassic. The most significant occurrence is Poços de Caldas, the largest alkaline massif in South America. In general, these agpaitic rocks contain mineral assemblages that indicate presence of typical halogen-bearing Na–Ca–HFSE phases, eudialyte-, rinkite- and wöhlerite-group minerals being the most frequent ones. However, these associations are indeed more complex in terms of composition, with accessory phases in some cases consisting of various minerals, including U–Th oxides/silicates, Nb oxides, REE–Sr–Ba bearing carbonates–fluorocarbonates–phosphates–silicates and Zr–Na rich silicates. They usually form late magmatic stage to hydrothermal/deuteric assemblages linked with coarse and fine-grained, mainly silica-undersaturated evolved rocks. Data also indicate significant differences in type, amount and composition of agpaitic minerals in all investigated occurrences.
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Beiranvand Pour, Amin, Yongcheol Park, Laura Crispini, Andreas Läufer, Jong Kuk Hong, Tae-Yoon S. Park, Basem Zoheir et al. „Mapping Listvenite Occurrences in the Damage Zones of Northern Victoria Land, Antarctica Using ASTER Satellite Remote Sensing Data“. Remote Sensing 11, Nr. 12 (13.06.2019): 1408. http://dx.doi.org/10.3390/rs11121408.
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Listvenites normally form during hydrothermal/metasomatic alteration of mafic and ultramafic rocks and represent a key indicator for the occurrence of ore mineralizations in orogenic systems. Hydrothermal/metasomatic alteration mineral assemblages are one of the significant indicators for ore mineralizations in the damage zones of major tectonic boundaries, which can be detected using multispectral satellite remote sensing data. In this research, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) multispectral remote sensing data were used to detect listvenite occurrences and alteration mineral assemblages in the poorly exposed damage zones of the boundaries between the Wilson, Bowers and Robertson Bay terranes in Northern Victoria Land (NVL), Antarctica. Spectral information for detecting alteration mineral assemblages and listvenites were extracted at pixel and sub-pixel levels using the Principal Component Analysis (PCA)/Independent Component Analysis (ICA) fusion technique, Linear Spectral Unmixing (LSU) and Constrained Energy Minimization (CEM) algorithms. Mineralogical assemblages containing Fe2+, Fe3+, Fe-OH, Al-OH, Mg-OH and CO3 spectral absorption features were detected in the damage zones of the study area by implementing PCA/ICA fusion to visible and near infrared (VNIR) and shortwave infrared (SWIR) bands of ASTER. Silicate lithological groups were mapped and discriminated using PCA/ICA fusion to thermal infrared (TIR) bands of ASTER. Fraction images of prospective alteration minerals, including goethite, hematite, jarosite, biotite, kaolinite, muscovite, antigorite, serpentine, talc, actinolite, chlorite, epidote, calcite, dolomite and siderite and possible zones encompassing listvenite occurrences were produced using LSU and CEM algorithms to ASTER VNIR+SWIR spectral bands. Several potential zones for listvenite occurrences were identified, typically in association with mafic metavolcanic rocks (Glasgow Volcanics) in the Bowers Mountains. Comparison of the remote sensing results with geological investigations in the study area demonstrate invaluable implications of the remote sensing approach for mapping poorly exposed lithological units, detecting possible zones of listvenite occurrences and discriminating subpixel abundance of alteration mineral assemblages in the damage zones of the Wilson-Bowers and Bowers-Robertson Bay terrane boundaries and in intra-Bowers and Wilson terranes fault zones with high fluid flow. The satellite remote sensing approach developed in this research is explicitly pertinent to detecting key alteration mineral indicators for prospecting hydrothermal/metasomatic ore minerals in remote and inaccessible zones situated in other orogenic systems around the world.
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Li, Yuan, Wenhui Huang, Bo Jiu, Qilong Sun und Qingsong Che. „Modes of Occurrence and Origin of Minerals in Permian Coals from the Huainan Coalfield, Anhui, China“. Minerals 10, Nr. 5 (29.04.2020): 399. http://dx.doi.org/10.3390/min10050399.
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Minerals in coal provide useful information for not only paleo-environments of peat accumulation, but also for geological evolution during later diagenesis and/or epigenesis. This paper reports new data on coal quality and the mineralogical and geochemical compositions of 17 unaltered (by intrusion) coal samples collected from the Huainan coalfield, providing new insight into the origins and modes of occurrence of the minerals in coal and their geological evolution. The results showed that the studied coal samples were low rank bituminous coal, with low ash yield (11.92–38.31%, average 24.80%) and high volatile content (25.13–43.43%, average 37.29%). Minerals in the coal mainly included kaolinite and quartz; varying proportions of calcite, siderite, ankerite, and pyrite; and traces of chlorite, zircon, strontianite, apatite, and gorceixite. Typical modes of mineral occurrence could be used to determine the formation stage of minerals. The detrital mineral, occurring as sub-angular to rounded discrete fragments or thin layers intimately admixed with organic matter at particular horizons, was of terrigenous origin, deposited during peat accumulation. Cell infillings, as well as nodule siderites and polycrystalline aggregates of pyrite, precipitated during the syngenetic to early diagenetic stages. Cleat infillings, compressed cell infillings, and fracture infillings precipitated in the epigenetic stage. However, the stage of mineral formation of the pore infilling was difficult to determine. Combined with coal quality, mineralogy, and geochemical analysis, the sedimentary environment of Shanxi Formation was affected by seawater, and Fe-rich hydrothermal fluids filled into the No. 3 coal seam in the epigenetic stage. The sedimentary environment of the No. 8 coal seam had widespread reduction and acid conditions due to basin subsidence, and sulfate-rich hydrothermal fluids may have been formed during the peat deposition stage. In contrast, the peat accumulation environment of the Upper Shihezi Formation was oxidized with a low pH condition. Alkaline fluid then flowed into the No. 13-1 coal seam in the epigenetic stage.
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Ouyang, Liming, Jianqi Zhou, Huan Li, Majid Ghaderi, Wenbo Sun, Yiming Xie und Xiaofan Li. „Process Mineralogy of Lithium and Rubidium in the Diantan Polymetallic Mining Area, Tengchong, Southwest China“. Minerals 14, Nr. 4 (30.03.2024): 369. http://dx.doi.org/10.3390/min14040369.
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Highly differentiated granite often contains abundant key metal resources, such as lithium and rubidium. The Tengchong area of Yunnan hosts a large number of highly differentiated granites from the Cretaceous age. Among these, granite samples from the Diantan tin–lead–zinc polymetallic mining area exhibit Li contents exceeding 0.02% and Rb contents surpassing 0.1%. This suggests a promising potential for Li and Rb mineralization. However, the occurrence status and process mineralogical characteristics of Li and Rb remain unclear, directly impacting the assessment of the region’s comprehensive utilization potential for these key metals. This study focuses on representative granite samples from the Diantan mining area to conduct petrographic and process mineralogical research, examining single mineral chemical composition, physical properties, element occurrence state, and mineral embedding particle size. The results indicate that mica minerals primarily contain Li, while both feldspar and mica minerals are the main carriers of Rb. Zinnwaldite not only contains the highest Rb proportion among the samples but also plays a significant role in Li occurrence. Based on the dissociation characteristics, it is recommended to grind the material to a fineness of −0.075 mm, comprising 80% of the particles, before proceeding to the final flotation process. This would result in approximately 95% dissociation of the mica in the sample. Since mica is predominantly distributed between quartz and feldspar particles, with relatively low binding force, it facilitates mineral dissociation during the grinding process. Therefore, the actual beneficiation process may consider a moderately coarser grinding fineness based on the aforementioned findings.
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Rodgers, K. A., R. Greatrex, M. Hyland, S. F. Simmons und P. R. L. Browne. „A modern, evaporitic occurrence of teruggite, Ca4MgB12As2O28.18H2O, and nobleite, CaB6O10.4H2O, from the El Tatio geothermal field, Antofagasta Province, Chile“. Mineralogical Magazine 66, Nr. 2 (April 2002): 253–59. http://dx.doi.org/10.1180/0026461026620026.
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AbstractTeruggite is the dominant phase in a soft, off-white, poorly-layered and weakly-cemented surface crust, 10–15 mm thick, occurring in the high-temperature El Tatio geothermal field of Chile. Other minerals present include halite, which is present throughout but also forms a thin (<0.5 mm), brittle, cratered surface to the deposit, nobleite, ulexite and opal-A, with possible traces of illite-smectite and at least one unidentified phase. With the exception of ulexite, none of the minerals associated with teruggite at El Tatio has been reported from other occurrences of this mineral, nor do they occur with nobleite in its sole other known occurrence in Death Valley. EDS and XPS analyses of the main mass of the deposit show the presence of Ca, As, B, Na, and Cl, consistent with the identified mineral assemblage, but with elevated concentrations in Ca and Cl that are presumably associated with a further phase. Little Mg is present and the El Tatio teruggite appears deficient in this element, with Ca presumably replacing Mg in the structure. Unlike earlier documented occurrences of teruggite, that at El Tatio is evaporitic, modern and surficial. It is located some 50 m from the nearest hot (~50°C) pool and there is no evidence of association with fluid discharge. As such, the deposit has presumably derived from a fluid moving in the uppermost levels of the El Tatio field; perhaps a heavily modified version of the brines found in the deep wells.
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Sachkov, Victor Ivanovich, Roman Andreevich Nefedov, Rodion Olegovych Medvedev, Ivan Vyacheslavovich Amelichkin, Anna Sergeevna Sachkova, Pavel Sergeevich Shcherbakov, Vladislav Sergeevich Solovyev, Daniil Igorevich Leonov und Danil Aleksandrovich Biryukov. „Content and Forms of Radioactive Elements in Orthite (Allanite)“. Minerals 13, Nr. 3 (06.03.2023): 366. http://dx.doi.org/10.3390/min13030366.
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The present work analyzes the specimens of orthite (allanite) mineral ores obtained from the Vernadsky mine (Slyudyanka River, Irkutsk region) and Yuzhno-Bogatyrskoye occurrence (Kuznetsk Alatau). The elemental chemical composition of the ore was determined by electronic microscopy of the specimen’s surface. The study establishes that uranium and thorium in orthite ores of the Yuzhno-Bogatyrskoye occurrence are mainly represented by their separate minerals, while the content of the orthite phase in the form of their isomorphic inclusion is small.
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Zhou, Sandong, Dameng Liu, Yidong Cai, Yingjin Wang und Detian Yan. „Mineral Characteristics of Low-Rank Coal and the Effects on the Micro- and Nanoscale Pore-Fractures: A Case Study from the Zhundong Coalfield, Northwest China“. Journal of Nanoscience and Nanotechnology 21, Nr. 1 (01.01.2021): 460–71. http://dx.doi.org/10.1166/jnn.2021.18459.
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The mineral characteristics (occurrence, type, and content) of low-rank coal and their influence on coalbed methane (CBM) reservoirs are investigated at the micro- and nanoscales. Six coal samples of three representative coalmines were used to demonstrate the uniform tectonization from the Zhundong coalfield, NW China. Based on optical microscopy and scanning electron microscopyenergy dispersive spectrum (SEM-EDS) analysis, the mineral composition and occurrence characteristics were discussed. The micro- and nanoscale reservoir characteristics in low-rank coal (pore size distribution and adsorption capability) were studied by diverse methods, including lowtemperature N2 adsorption/desorption, mercury intrusion porosimetry and CH4 isotherm adsorption analysis. The coal reservoir nuclear magnetic T2 spectra of porosity and movable fluid were obtained by combining low-field nuclear magnetic resonance (NMR) analysis, which has an advantage of determining pore fluid technology. The mineral content is highly variable (4˜16 vol.%) in the Xi Heishan prospecting area of the Qitai region. Kaolinite, goyazite, ankerite and anorthosite were microscopically observed to be filling in coal pores and microfractures, and the minerals are given priority to silicate minerals. There is a greater content of mesopores (100–1000 nm) and transition pores (10–100 nm), and they are well connected. The micropores (0–10 nm) are dominated by parallel plate, closed or wedge-shaped pores. Furthermore, the microfractures are mainly observed for types B (width ≥ 5 μm and length≤ 10 mm) and D (width<5 μm and length<300 μm). The results show that microfractures B and C (width< 5 μm and length ≥ 300 μm) are better connected, but the orientation and connectivity of type D are worse. The Langmuir volume and mesopore content decreased with increasing mineral content, which shows that the low-rank coal minerals filled some adsorption space; the reduced CBM adsorption capacity and cellular pore and intergranular pore filled with minerals affect the mesopore content. Therefore, mineral characterization significantly influences methane adsorption capacity and pore structure.
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Sundal, Anja, und Helge Hellevang. „Using Reservoir Geology and Petrographic Observations to Improve CO2 Mineralization Estimates: Examples from the Johansen Formation, North Sea, Norway“. Minerals 9, Nr. 11 (31.10.2019): 671. http://dx.doi.org/10.3390/min9110671.
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Reservoir characterization specific to CO2 storage is challenging due to the dynamic interplay of physical and chemical trapping mechanisms. The mineralization potential for CO2 in a given siliciclastic sandstone aquifer is controlled by the mineralogy, the total reactive surface areas, and the prevailing reservoir conditions. Grain size, morphologies and mineral assemblages vary according to sedimentary facies and diagenetic imprint. The proposed workflow highlights how the input values for reactive mineral surface areas used in geochemical modelling may be parameterized as part of geological reservoir characterization. The key issue is to separate minerals both with respect to phase chemistry and morphology (i.e., grain size, shape, and occurrence), and focus on main reactants for sensitivity studies and total storage potentials. The Johansen Formation is the main reservoir unit in the new full-value chain CO2 capture and storage (CCS) prospect in Norway, which was licenced for the storage of CO2 as of 2019. The simulations show how reaction potentials vary in different sedimentary facies and for different mineral occurrences. Mineralization potentials are higher in fine-grained facies, where plagioclase and chlorite are the main cation donors for carbonatization. Reactivity decreases with higher relative fractions of ooidal clay and lithic fragments.
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Mahaffey, Nova, und Robert B. Finkelman. „The Extraordinary Variety and Complexity of Minerals in a Single Keokuk Geode from the Lower Warsaw Formation, Hamilton, Illinois, USA“. Minerals 12, Nr. 7 (21.07.2022): 914. http://dx.doi.org/10.3390/min12070914.
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We performed an extensive optical and chemical analysis of a single Keokuk geode using electron microscopy (SEM) with energy dispersive X-ray (EDX) spectroscopy that revealed an extraordinary array of minerals and multiple, complex cycles of mineralization. We identified at least 15 minerals including 5 that, to our knowledge, have not been reported in previous studies of these geodes. Along with bitumen we have described the occurrence of REE’s, and other unidentified phases containing metals such as chromium, nickel, molybdenum, tin, copper, zinc, and lead. Additionally, preliminary thin-section analysis reveals the occurrence of the tentatively identified minerals zircon, rutile, and xenotime as well as grains containing gold and silver within the chalcedony shell. The presence of these potentially economically valuable minerals warrants further investigation into the micro-minerology of Keokuk geodes. Our SEM/EDX analysis reveals an array of complex mineral assemblages, intergrowths, and inclusions that help chronologically link multiple stages of paragenesis occurring in different locations within the geode. Consequently, morphology and intricate microstructures provide a window into the extreme complexity of mineral crystallization. The majority of micro-minerals we have observed correspond with the later stages of geode paragenesis, thus providing a detailed record of the secondary mineralization processes which occurred over thousands to millions of years.
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Chung, C. J., und A. G. Fabbri. „Mineral Occurrence Target Mapping: A General Iterative Strategy in Prediction Modeling for Mineral Exploration“. Natural Resources Research 29, Nr. 1 (15.05.2019): 115–34. http://dx.doi.org/10.1007/s11053-019-09494-5.
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Takhirjanovich, Razikov Odil. „Genetic Types Of Rare Mineral Gold Of Western Uzbekistan (Southern Tien-Shan)“. American Journal of Applied sciences 02, Nr. 12 (27.12.2020): 61–67. http://dx.doi.org/10.37547/tajas/volume02issue12-10.
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The work describes the genetic types and conditions for the localization of mineralization - individual deposits and ore occurrences. Also, the indicated mineralized zones, the conditions of occurrence of the mineralization, the geological-structural position and the peculiarities of the host complexes. Descriptions of promising tungsten, tin ore, polymetallic, mercury and other ore zones, which serve as a reserve in expanding the resource base in the Republic, are given. Tungsten, tin ore, and mercury mineralizations are characterized in somewhat more detail, since the latter in the region under study is often spatially associated with gold and forms mercury-antimony-polymetallic mineralization.
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Melodi, M. M., M. A. Gbolagade, J. O. Amigun und O. C. Alaba. „Statistical Investigation of the Relationship between Gold and Associate Minerals: A case Study of Kagara Area of Niger State Nigeria Soil“. International Journal of Engineering and Advanced Technology Studies 11, Nr. 1 (15.01.2023): 1–18. http://dx.doi.org/10.37745/ijeats.13/vol11n1118.
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In the Kagara region of Niger State, north-central Nigeria, an investigation was conducted into the gold occurrence and availability of other economic-benefit associate minerals. 39 samples from the study area were subjected to fire assay analysis and multi-element analysis to determine the gold and other mineral recovery in the case study formation. Statistical examination Methods of Pearson correlation and R-mode varimax rotated factor analysis were used to interpret the results. The analysis revealed that the recovered gold (Au) had a grade between 0.01g per tonne and 0.19g per tonne. Li was also identified as the associate mineral with the lowest quantity, with a range of 1-20% and a mean value of 8.49%, whereas Manganes displayed some skewness with a minimum value of 156 and a maximum value of 3080 ppm. According to the Pearson correlation analysis, Lithium and Magnesium have a moderately positive correlation, indicating that they come from the same source. In addition, Mo and Ni have a strong positive correlation whereas Au and Na have a weak positive correlation. The factor analysis performed on the gold and associated mineral occurrences revealed that the deposit had been significantly altered by both environmental and mineralization factors in the study area's soil. Importantly, the study demonstrates that an associated mineral with gold has substantial economic value. Considering the capital and operating costs required for the exploration and exploitation of gold-bearing soil and rock, it has been determined that the refining of other associate minerals to improve the cost-benefit ratio is highly advantageous.
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Mao, Song, und Qin Zhang. „Mineralogical Characteristics of Phosphate Tailings for Comprehensive Utilization“. Advances in Civil Engineering 2021 (31.03.2021): 1–13. http://dx.doi.org/10.1155/2021/5529021.
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The mineralogical characteristics of a phosphate tailing were studied, and the occurrence state, mineral types, and embedded characteristics of phosphorus in the phosphate tailings were ascertained. The results show that the main minerals in the phosphate tailings are collophane. The main gangue minerals are quartz, dolomite, calcite, a small amount of potassium feldspar, plagioclase, chlorite, etc. Monazite was found in phosphate tailings. In addition, the coarse grain size of quartz and feldspar and fine embedded particle size of calcite and dolomite are also the main factors affecting the mineral processing of phosphate tailings. According to the analysis of mineralogical characteristics, the physical and chemical properties of phosphate tailings provided the basis for comprehensive utilization of phosphorus resources.
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Murzin, Valery, Galina Palyanova, Татiana Mayorova und Tatiana Beliaeva. „The Gold–Palladium Ozernoe Occurrence (Polar Urals, Russia): Mineralogy, Conditions of Formation, Sources of Ore Matter and Fluid“. Minerals 12, Nr. 6 (16.06.2022): 765. http://dx.doi.org/10.3390/min12060765.
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We studied the mineralization and sulfur isotopic composition of sulfides of gold–palladium ores in olivine clinopyroxenites from the Dzelyatyshor massif made up of a continuous layered series of rocks: olivine-free clinopyroxenite–olivine clinopyroxenite–wehrlite. The primary igneous layering of rocks, manifested as different quantitative ratios of clinopyroxene and olivine in them, controls the local trends of variability in the chemistry of mineral-forming medium and the concentrations of ore components, including noble metals, and sulfur in each separate layer during its cooling. The replacement of primary rock-forming minerals by secondary minerals, when the temperature decreases, is a characteristic trend for pyroxenites: (a) olivine → serpentine, secondary magnetite, and (b) clinopyroxene → amphibole, secondary magnetite → chlorite. The deposition of native gold in parageneses with PGM and sulfides at the Ozernoe occurrence took place during the replacement of earlier rock-forming minerals by chlorite. This process completed mineral formation at the deposit and took place at temperatures 150–250 °С and at the high activity of S, Te, Sb, and As of fluid. The variability of mineral formation conditions during chloritization is reflected in the change of native-sulfide forms of Pd by arsenide-antimonide forms and the sulfur isotopic composition of sulfides. The Pd content in native gold increases in the series—Au-Ag solid solution (<1.5 wt.% Pd)—Au-Cu intermetallides (to 6 wt.% Pd)—Cu-Au-Pd solid solutions (16.2–16.9 wt.% Pd). The sulfur isotopic composition of pyrite, chalcopyrite, and bornite varies from −2.1 to −2.9‰. It is assumed that a deep-seated magmatic basic melt was the source of fluid, ore components, and sulfur.