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Minerals, Volume 12, Issue 9 (September 2022) – 118 articles

Cover Story (view full-size image): The Dinaridic Ozren ophiolite complex in Bosnia and Herzegovina contains troctolites replacing dunite layers in harzburgite. Troctolite is crosscut by doleritic and plagioclase(Pl)-rich dykes and veins. The secondary Pl enrichment of dunite (relic black pods) reflets a Pl-clinopyroxene(Cpx) melt impregnation of dunite. Microscopic and back-scattered-electron images from troctolite document newly formed plagioclase Pl and Cpx enclosing olivine (Ol) and spinel (Spl) of dunite. The secondary phases are amphibole (Amp), phlogopite (Phl), albite (Ab) and strontianite (Str). The percolating melt was likely formed by decompression and partial melting of a refractory peridotite in the asthenosphere and via a reaction of this melt with peridotite at the base of the thinning thermal lithosphere. View this paper
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17 pages, 5756 KiB  
Article
Chlorellestadite (Synth): Formation, Structure, and Carbonate Substitution during Synthesis of Belite Clinker from Wastes in the Presence of CaCl2 and CO2
by Krassimir Garbev, Angela Ullrich, Günter Beuchle, Britta Bergfeldt and Peter Stemmermann
Minerals 2022, 12(9), 1179; https://doi.org/10.3390/min12091179 - 19 Sep 2022
Cited by 3 | Viewed by 1550
Abstract
The synthesis of low-temperature belite (C2S) clinker from wastes of autoclaved aerated concrete and limestone was studied in the presence of CaCl2 as a mineralizing agent. Synthetic chlorellestadite (SCE; Ca10(SiO4)3(SO4)3Cl [...] Read more.
The synthesis of low-temperature belite (C2S) clinker from wastes of autoclaved aerated concrete and limestone was studied in the presence of CaCl2 as a mineralizing agent. Synthetic chlorellestadite (SCE; Ca10(SiO4)3(SO4)3Cl2) forms in experiments at temperatures between 700 and 1200 °C. Samples were investigated by X-ray diffraction and Raman spectroscopy. In general, the amount of SCE depends mainly on the sulfate content and to a lesser extent on the synthesis temperature. At lower temperatures of formation, a non-stoichiometric SCE seems to crystallize in a monoclinic symmetry similar to hydroxylellestadite. Rietveld refinements revealed the presence of chlorine and calcium vacancies. Raman spectroscopy proved the partial substitution of sulfate by CO32− groups in ellestadites formed at 800 °C and 900 °C in air. Incorporation of CO3 results in a shorter unit cell parameters and smaller cell volume similar to CO3−apatite. At low temperatures, SCE coexists with spurrite intermixed on a very fine nm scale. At temperatures above 900 °C in air, ellestadite is carbonate-free and above 1000 °C chlorine loss starts in all samples. Full article
(This article belongs to the Special Issue Cement Related Minerals—in Memory of Herbert Pöllmann)
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20 pages, 23764 KiB  
Article
Exploring High-Resolution Chemical Distribution Maps of Incompatible and Scarce Metals in a Nepheline Syenite from the Massif of “Serra de Monchique” (Portugal, Iberian Peninsula)
by Sofia Barbosa, António Dias, Diogo Durão, José Grilo, Gonçalo Baptista, Jonhsman Cagiza, Sofia Pessanha, Joaquim Simão and José Almeida
Minerals 2022, 12(9), 1178; https://doi.org/10.3390/min12091178 - 19 Sep 2022
Cited by 1 | Viewed by 1474
Abstract
In this case study, 2D micro energy dispersive X-ray fluorescence (µ-EDXRF) surveys were performed in the nepheline syenite (NS) of “Serra de Monchique” located in the southwest region of Portugal (Algarve, Iberian Peninsula). The results allow the identification in the mineral matrix of [...] Read more.
In this case study, 2D micro energy dispersive X-ray fluorescence (µ-EDXRF) surveys were performed in the nepheline syenite (NS) of “Serra de Monchique” located in the southwest region of Portugal (Algarve, Iberian Peninsula). The results allow the identification in the mineral matrix of certain elements classified as critical raw materials (CRMs). Due to substitution effects, some scarce transition elements, such as Zn and Ni, are present and camouflaged in alkali silicate minerals, while others, such as Co, are included in ferromagnesian mineral phases. As expected, incompatible elements are preferably distributed on the surface of aluminosilicate mineral phases such as Rb and Ga, or exclusively in K-bearing feldspar phases, as it is the case of Sr. Interesting CRMs such as Ti, Zr, and Nb are well individualized in oxides, as well as in sphene and apatite. The detected antagonistic chemical distribution between Ti and Fe, and the good spatial relation between Ti and Ca confirms that Ti is present as sphene and, in areas with absent Si, probably occurs as rutile. Nb has a distribution pattern quite similar to Zr and occurs due to substitution effects. It was possible to conclude that there is probable co-existence of Zr-REE-Nb in specific mineral phases such as apatite, zircon, and other Zr-oxides. These results evidence and confirm NS as a potential source of multiple industrial minerals and distinct scarce elements which are incorporated in oxide or phosphate phases that can be more effectively separated in the beneficiation process. Full article
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23 pages, 3630 KiB  
Review
Advances in Pulsed Power Mineral Processing Technologies
by Valentine A. Chanturiya and Igor Zh. Bunin
Minerals 2022, 12(9), 1177; https://doi.org/10.3390/min12091177 - 19 Sep 2022
Cited by 4 | Viewed by 2281
Abstract
In Russia and globally, pulsed power technologies have been proposed based on the conversion of energy into a short-pulsed form and exposing geomaterials (minerals, rocks, and ores) to strictly dosed high-power pulsed electric and magnetic fields, beams of charged particles, microwave radiation, neutrons [...] Read more.
In Russia and globally, pulsed power technologies have been proposed based on the conversion of energy into a short-pulsed form and exposing geomaterials (minerals, rocks, and ores) to strictly dosed high-power pulsed electric and magnetic fields, beams of charged particles, microwave radiation, neutrons and X-ray quanta, and low-temperature plasma flows. Such pulsed energy impacts are promising methods for the pretreatment of refractory mineral feeds (refractory ores and concentration products) to increase the disintegration, softening, and liberation performance of finely disseminated mineral complexes, as well as the contrast between the physicochemical and process properties of mineral components. In this paper, we briefly review the scientific foundations of the effect of both high-power nanosecond electromagnetic pulses (HPEMP) and dielectric barrier discharge (DBD) in air on semiconductor ore minerals (sulfides, rare metals minerals) and rock-forming dielectric minerals. The underlying mechanisms of mineral intergrowth disintegration and changes in the structural and chemical states of the mineral surface when exposed to HPEMP and DBD irradiation are discussed. The high performance and potential limitations of pulsed energy impact and low-temperature plasma produced by DBD treatment of geomaterials are discussed in terms of the directional change in the process properties of the minerals to improve the concentration performance of refractory minerals and ores. Full article
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14 pages, 8442 KiB  
Article
The Analysis of Bio-Precursor Organic Matter Compositions and Its Significance for Gas Shale Reservoir of Wufeng–Longmaxi Formation from Dingshan Area, Sichuan Basin
by Zhihong Wang, Xiaomin Xie, Zhigang Wen, Yaohui Xu and Yan Liu
Minerals 2022, 12(9), 1176; https://doi.org/10.3390/min12091176 - 19 Sep 2022
Viewed by 1110
Abstract
In order to analyze the organic matter (OM) composition, this study carefully identified the OM types of 66 samples from Well A in the Dingshan area under microscope, and made an effort to obtain the semi-quantitative statistics contents of different bio-precursor derived OM. [...] Read more.
In order to analyze the organic matter (OM) composition, this study carefully identified the OM types of 66 samples from Well A in the Dingshan area under microscope, and made an effort to obtain the semi-quantitative statistics contents of different bio-precursor derived OM. The results of OM content obtained under microscope showed a strong positive relationship (R2 = 0.85) with the TOC content analyzed by carbon–sulfur analyzer. The OM contained bethic algae debris, phytoplankton amorphous organic matter (AOM), acritarch, vitrinite-like particles, zooplankton (including graptolite, chitinozoa and others) and solid bitumen which was secondary formation OM. The phytoplankton AOM, graptolite and solid bitumen were the dominated OM in this interval. Solid bitumen (8%~11%) was filled at the bottom of the Wufeng Formation, which could be one reason for the high shale gas production in the lower part of this shale interval. N2 adsorption results showed that micropores and mesopores were predominant in this shale gas system, while pore volumes illustrated better positive relationships with organic matter than minerals, especially AOM content. Thus, both solid bitumen and AOM kerogen were the main sources for shale gas generation in this shale gas system. Full article
(This article belongs to the Special Issue Shale and Tight Reservoir Characterization and Resource Assessment)
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15 pages, 4094 KiB  
Article
Evaluation of the Shrinkage Produced with the Use of Cements with Pozzolanic Additions in the Production of Concrete
by Maria Betania Diaz-Garcia, Yosvany Diaz-Cardenas, Juan Ribalta-Quesada and Fernando Martirena-Hernandez
Minerals 2022, 12(9), 1175; https://doi.org/10.3390/min12091175 - 19 Sep 2022
Cited by 1 | Viewed by 1133
Abstract
Early age cracking in concrete is caused by a combination of the chemical and autogenous shrinkage caused by the exhaustion of the water in the pores during the hydration of cement phases. Generally, this process takes place in the first 72 h of [...] Read more.
Early age cracking in concrete is caused by a combination of the chemical and autogenous shrinkage caused by the exhaustion of the water in the pores during the hydration of cement phases. Generally, this process takes place in the first 72 h of concrete casting. The use of supplementary cementitious materials (SCMs) can mitigate cracking due to several factors, among them: dilution effect, provision of extra nucleation sites due to the high specific surface of the SCMs, and the increased water retention associated with the presence of fine SCMs. This paper compares the impact of two SCMs systems on early age cracking of the following concretes: (i) pozzolanic cement with natural pozzolan (zeolite) and (ii) a ternary binder limestone-calcined clay cement (LC3). The study was Carried out on cement paste and concrete. The addition of calcined clay and limestone decreases early age cracking better than in any other system, including the Portland-pozzolan system. It is related to a lower clinker factor and improved hydration of the system, and a better-developed microstructure at early ages due to the energetic reaction of the alumina phase C3A, enhanced by the extra alumina (Al2O3) provided by the calcined clay. Full article
(This article belongs to the Special Issue Blended Cements Incorporating Calcined Clay and Limestone)
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14 pages, 4302 KiB  
Article
Three-Dimensional Mineral Prospectivity Modeling for Delineation of Deep-Seated Skarn-Type Mineralization in Xuancheng–Magushan Area, China
by Fandong Meng, Xiaohui Li, Yuheng Chen, Rui Ye and Feng Yuan
Minerals 2022, 12(9), 1174; https://doi.org/10.3390/min12091174 - 18 Sep 2022
Cited by 4 | Viewed by 1987
Abstract
The Middle–Lower Yangtze River Metallogenic Belt is an important copper and iron polymetallic metallogenic belt in China. Today’s economic development is inseparable from the support of metal mineral resources. With the continuous exploitation of shallow and easily identifiable mines in China, the prospecting [...] Read more.
The Middle–Lower Yangtze River Metallogenic Belt is an important copper and iron polymetallic metallogenic belt in China. Today’s economic development is inseparable from the support of metal mineral resources. With the continuous exploitation of shallow and easily identifiable mines in China, the prospecting work of deep and hidden mines is very important. Mineral prospectivity modeling (MPM) is an important means to improve the efficiency of mineral exploration. With the increase in resource demands and exploration difficulty, the traditional 2DMPM is often difficult to use to reflect the information of deep mineral deposits. More large-scale deposits are needed to carry out 3DMPM research. With the rise of artificial intelligence, the combination of machine learning and geological big data has become a hot issue in the field of 3DMPM. In this paper, a case study of 3DMPM is carried out based on the Xuancheng–Magushan area’s actual data. Two machine learning methods, the random forest and the logistic regression, are selected for comparison. The results show that the 3DMPM based on random forest method performs better than the logistic regression method. It can better characterize the corresponding relationship between the geological structure combination and the metallogenic distribution, and the accuracy in the test set reaches 96.63%. This means that the random forest model could provide more effective and accurate support for integrating predictive data during 3DMPM. Finally, five prospecting targets with good metallogenic potential are delineated in the deep area of the Xuancheng–Magushan area for future exploration. Full article
(This article belongs to the Special Issue 3D/4D Geological Modeling for Mineral Exploration)
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33 pages, 9288 KiB  
Article
Construction and Application of a Knowledge Graph for Gold Deposits in the Jiapigou Gold Metallogenic Belt, Jilin Province, China
by Yao Pei, Sheli Chai, Xiaolong Li, Jofrisse Cremilda Samuel, Chengyou Ma, Haonan Chen, Renxing Lou and Yu Gao
Minerals 2022, 12(9), 1173; https://doi.org/10.3390/min12091173 - 17 Sep 2022
Viewed by 1783
Abstract
Over the years, many geological exploration reports and considerable geological data have been accumulated during the prospecting and exploration of the Jiapigou gold metallogenic belt (JGMB). It is very important to fully utilize these geological and mineralogical big data to guide future gold [...] Read more.
Over the years, many geological exploration reports and considerable geological data have been accumulated during the prospecting and exploration of the Jiapigou gold metallogenic belt (JGMB). It is very important to fully utilize these geological and mineralogical big data to guide future gold exploration. This work collects the original textual data of different gold deposits in JGMB and constructs a knowledge graph (KG) for deposits based on deep learning (DL) and natural language processing (NLP). Based on the metallogenic geological characteristics of deposits, a visual construction method of a KG for deposits and a calculation of the similarity between deposits are proposed. In this paper, 20 geological entities and 24 relationship categories are considered. By condensing the key KG information, the metallogenic geological conditions and factors controlling the ore in 14 typical deposits in the JGMB are systematically analyzed, and the metallogenic regularity is summarized. By calculating the deposits’ cosine similarities based on the KG, the mineralization types of deposits can be divided into two categories according to the industrial types of ore bodies. The results also show that the KG is a cutting-edge technology that can extract the rich information of ore-forming regularity and prospecting criteria contained in the textual data to help researchers quickly analyze the mineralization information. Full article
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18 pages, 3925 KiB  
Article
Numerical Simulation Study on the Relationships between Mineralized Structures and Induced Polarization Properties of Seafloor Polymetallic Sulfide Rocks
by Caowei Wu, Changchun Zou, Cheng Peng, Yang Liu, Tao Wu, Jianping Zhou and Chunhui Tao
Minerals 2022, 12(9), 1172; https://doi.org/10.3390/min12091172 - 17 Sep 2022
Viewed by 1261
Abstract
The induced polarization (IP) method plays an important role in the detection of seafloor polymetallic sulfide deposits. Numerical simulations based on the Poisson–Nernst–Planck equation and the Maxwell equation were performed. The effects of mineralized structures on the IP and electrical conductivity properties of [...] Read more.
The induced polarization (IP) method plays an important role in the detection of seafloor polymetallic sulfide deposits. Numerical simulations based on the Poisson–Nernst–Planck equation and the Maxwell equation were performed. The effects of mineralized structures on the IP and electrical conductivity properties of seafloor sulfide-bearing rocks were investigated. The results show that total chargeability increases linearly as the volume content of disseminated metal sulfides increases when the volume content is below 20%. However, total chargeability increases nonlinearly with increasing volume content in vein and massive metal sulfides when the volume content is below 30%. The electrical resistivity of disseminated metal sulfides mainly depends on the conductivity of pore water. The electrical resistivity of vein and massive sulfides mainly depends on the volume content and the length of sulfides. Increase in the aspect ratio (0.36 to 0.93) of seafloor massive sulfides causes relaxation time constants and total chargeability to decrease. Relaxation time constants and total chargeability also decrease with increase in the tortuosity of seafloor vein sulfides from 1.0 to 1.38. This study is of great value for the electrical survey of seafloor polymetallic sulfide deposits. Full article
(This article belongs to the Special Issue Development Methods and Technologies Used in Deep-Sea Mining)
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3 pages, 225 KiB  
Editorial
First-Principles Calculations of Minerals and Related Materials
by Jordi Ibáñez-Insa
Minerals 2022, 12(9), 1171; https://doi.org/10.3390/min12091171 - 16 Sep 2022
Viewed by 997
Abstract
As stated in their announcements and accompanying information, Special Issues published in scientific journals are usually aimed at compiling recent progress on highly specialized topics [...] Full article
(This article belongs to the Special Issue First Principles Calculations of Minerals and Related Materials)
16 pages, 4112 KiB  
Article
The Challenge of Grinding Ternary Blends Containing Calcined Clays and Limestone
by Juan Francisco Garces-Vargas, Yosvany Díaz-Cardenas, Franco Zunino, Juan Ribalta-Quesada, Karen Scrivener and Fernando Martirena
Minerals 2022, 12(9), 1170; https://doi.org/10.3390/min12091170 - 16 Sep 2022
Cited by 3 | Viewed by 2012
Abstract
The inclusion of high specific surface materials such as calcined clays in cementitious systems enhances the hydration of clinker products at very early ages, but it may also increase water demand; thus, the pursuit of a flowing concrete may demand an increase in [...] Read more.
The inclusion of high specific surface materials such as calcined clays in cementitious systems enhances the hydration of clinker products at very early ages, but it may also increase water demand; thus, the pursuit of a flowing concrete may demand an increase in the dosage of superplasticizers. The grinding regime can have a major influence on the properties of the cementitious system and could help mitigate the problem of water demand. This paper discusses the impact of grinding alternatives for the production of a binder consisting of clinker, calcined clay, limestone and gypsum. Two main target products will be discussed: (i) LC3, a binder with a formulation of 50% clinker, 30% calcined clay, 15% limestone and 5% gypsum, co-ground all together, and (ii) LC2, a mineral addition with a formulation of 60% calcined clay, 35% limestone and 5% gypsum, ground separately and further blended with Portland cement on a 1:1 basis (mass). The experimental program is carried out in several stages: (i) the binder, (ii) cement pastes and (iii) standard mortars, and concrete grinding aids from the family TEA are used to enhance grinding, and their impact is also be assessed. Full article
(This article belongs to the Special Issue Blended Cements Incorporating Calcined Clay and Limestone)
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30 pages, 12290 KiB  
Article
The Evolution of Permian Source-to-Sink Systems and Tectonics Implications in the NW Junggar Basin, China: Evidence from Detrital Zircon Geochronology
by Xingyu Chen, Zhijie Zhang, Xuanjun Yuan, Li Wan, Chuanmin Zhou, Yinhe Liu and Dawei Cheng
Minerals 2022, 12(9), 1169; https://doi.org/10.3390/min12091169 - 15 Sep 2022
Cited by 2 | Viewed by 1335
Abstract
The basin type of the Junggar Basin changed during the Permian, but the time constraint of the tectonic evolution remains unclear. Besides, the fan deltas developed in the Permian in the Mahu Sag in the northwestern of the oil-rich basin. However, the provenances [...] Read more.
The basin type of the Junggar Basin changed during the Permian, but the time constraint of the tectonic evolution remains unclear. Besides, the fan deltas developed in the Permian in the Mahu Sag in the northwestern of the oil-rich basin. However, the provenances of the sedimentary systems remain unclear. Based on petrology and detrital zircon U-Pb ages, this study investigates the source-to-sink systems evolution and tectonics implications. Abundant lithic clasts in sandstones with low compositional and textural maturity imply proximal sources. The dating results showed a dominant peak (310–330 Ma) and a secondary peak (400–440 Ma) in the northern Mahu Sag, only one peak at 295–325 Ma in the central Mahu Sag, several peaks at 270–350 Ma in the southern Mahu Sag, and multiple peaks at 370–450 Ma in the Zhongguai Uplift. Thus, the north-western Junggar Basin was divided into four major source-to-sink systems, with adjacent central West Junggar as the main provenance and northern and southern West Junggar as the secondary provenance. The proportion of sediment supply from the southern and northern West Junggar is higher during the Middle-Late Permian. It suggests that the source-to-sink systems show inheritance and evolve from a single provenance into a complex provenance, indicating the uplift of West Junggar. The tectonic inversion may occur early in the Middle Permian and the response to tectonic activity is stronger in the southern West Junggar than in the northern West Junggar. Full article
(This article belongs to the Section Mineral Geochemistry and Geochronology)
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17 pages, 5965 KiB  
Article
Macro-Microscopic Deterioration Behavior of Gypsum Rock after Wetting and Its Constitutive Model Based on Acoustic Emission
by Xiaoding Xu, Yuejin Zhou, Weiqiang Chen, Yubing Gao, Qiang Fu, Xue Liu and Chundi Feng
Minerals 2022, 12(9), 1168; https://doi.org/10.3390/min12091168 - 15 Sep 2022
Cited by 7 | Viewed by 1599
Abstract
Gypsum rock is highly sensitive to a water environment due to its unique physical and chemical properties, such as high solubility. After wetting, the internal microstructure of gypsum rock is damaged, and the mechanical properties deteriorate accordingly, leading to serious engineering problems for [...] Read more.
Gypsum rock is highly sensitive to a water environment due to its unique physical and chemical properties, such as high solubility. After wetting, the internal microstructure of gypsum rock is damaged, and the mechanical properties deteriorate accordingly, leading to serious engineering problems for gypsum-bearing geotechnical structures. Therefore, it is particularly necessary to investigate the mechanical deterioration behavior of gypsum rock after wetting. In this paper, the mechanical behavior of gypsum rocks with different water contents were studied. The relationship between the rock water content and the water immersion time was established through the water content test. The scanning electron microscope (SEM) images of the gypsum rock after the water immersion showed that the internal microstructure of the gypsum rock became looser and more complex as the immersion time increased. The fractal dimensions of the SEM images were calculated to quantify the degree of damage to the gypsum rocks after wetting. These images showed that the degree of damage increased with the increasing immersion time, but the increase rate tended to be slow. The relationship between the rock water content and the mechanical responses of gypsum rock were established by triaxial compression tests, and the concomitant acoustic emission (AE) characteristics in the loading processes showed that the immersion time had a positive correlation with the AE frequency and a negative correlation with the AE cumulative count. Based on the AE characteristics, a damage constitutive model of gypsum rock as a function of immersion time was developed and this can reproduce the mechanical responses of gypsum rock after wetting. Full article
(This article belongs to the Topic Support Theory and Technology of Geotechnical Engineering)
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18 pages, 5518 KiB  
Article
The Effects of Hydrochloric Acid Pretreatment on Different Types of Clay Minerals
by Bin Hu, Chunxia Zhang and Xiaoyan Zhang
Minerals 2022, 12(9), 1167; https://doi.org/10.3390/min12091167 - 15 Sep 2022
Cited by 6 | Viewed by 2696
Abstract
Clay minerals are common in geological samples and are useful paleoclimate and sediment provenance proxies. Acid pretreatment is the most common method for the separation and purification of clay minerals. Given that hydrochloric acid (HCl) can dissolve chlorite and distinguish it from kaolinite, [...] Read more.
Clay minerals are common in geological samples and are useful paleoclimate and sediment provenance proxies. Acid pretreatment is the most common method for the separation and purification of clay minerals. Given that hydrochloric acid (HCl) can dissolve chlorite and distinguish it from kaolinite, the HCl digestion method is used to simplify the routine method of clay mineral analysis. However, there have been few studies of the effects of acid digestion on different clay minerals in the context of extracting paleoclimate indicators. In this study, we used illite, chlorite, kaolinite, and two types of smectite to assess the effects of pretreatment with different HCl concentrations at variable temperatures. Our results show that chlorite is the most soluble clay mineral in HCl and can be effectively dissolved in HCl with concentrations of >1 N. The variable crystal structure of smectite affects its solubility in HCl. Ca-rich smectite, which has more cation substitution of octahedral Al, can be dissolved with HCl. However, Na-rich smectite, which has less cation substitution for octahedral Al, is hardly dissolved in HCl of any concentration or at any temperature. Illite can be partly dissolved in HCl, and the threshold beyond which dissolution occurs is 5 N HCl at 70 °C. Kaolinite is relatively difficult to dissolve in HCl. Given that the HCl digestion method uses the peak intensity of the bulk sample X-ray diffraction (XRD) analysis, whereas the routine method uses the peak area of clay particles, we compared the results of clay mineral quantification and the paleoclimate proxy obtained using the two methods for synthetically prepared mixed and natural clay samples. The results obtained with the HCl digestion method are less accurate than those obtained with the routine method because of the dissolution of illite and smectite in HCl. Therefore, the HCl pretreatment method is not suitable for clay mineral analysis in paleoclimate studies. The present results provide reference data for future studies that employ the acid dissolution pretreatment of clay mineral samples to acquire and quantify paleoclimate proxies. Full article
(This article belongs to the Section Clays and Engineered Mineral Materials)
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28 pages, 54990 KiB  
Article
Spatio-Temporal Evolution of the Crustal Uplift in Eastern NE China: Constraint from Detrital Zircon Ages of Late Mesozoic Clastic Rocks in the Boli Basin
by Song He, Hong Cheng, Shuangqing Li, Cong Cao, Jun He and Fukun Chen
Minerals 2022, 12(9), 1166; https://doi.org/10.3390/min12091166 - 15 Sep 2022
Cited by 1 | Viewed by 1419
Abstract
Detrital zircon of clastic rocks has been widely recognized as a powerful tool for the study of crustal uplift, which is of great significance for understanding multi-sphere interaction. However, young detrital zircons can only roughly constrain the depositional time of the strata, and [...] Read more.
Detrital zircon of clastic rocks has been widely recognized as a powerful tool for the study of crustal uplift, which is of great significance for understanding multi-sphere interaction. However, young detrital zircons can only roughly constrain the depositional time of the strata, and commonly used zircon age probability density and kernel density estimations cannot provide sufficient evidence to reveal spatio-temporal differences in tectonic uplift. The basins developed in active continental margins usually contain abundant magmatic rocks, which can provide insights into basin evolution and crustal deformation when combined with sedimentary characteristics. In this study, we report detrital zircon ages of Late Mesozoic clastic rocks from the Boli Basin, being part of the Great Sanjiang Basin Group in eastern NE China, which is strongly affected by the Paleo-Pacific subduction. In conjunction with the age data of coeval magmatic rocks and potential sedimentary sources of basement rocks adjacent to the basin, the geochronologic results of this study provide solid evidence for the formation of the Boli Basin and the spatio-temporal evolution of the crustal uplift in northeastern China. The Boli Basin went through multi-phase tectonic evolution of syn-rift and post-rift stages, based on the zircon age data of clastic and igneous rocks. When the geographical distribution characteristics of potential sedimentary sources and their percentages of contribution are taken into account, two stages of eastward migration of the crustal uplift and two episodes of basin destruction caused by the tectonic extension and subsequent compression can be proposed for the Boli Basin. These processes were caused successively by the rolling back of the subducted Paleo-Pacific slab, the docking of the Okhotomorsk block along the eastern continental margin of East Asia, and the transition of the subduction zone by the collision of the Okhotomorsk block. Full article
(This article belongs to the Special Issue Geological Evolution of The Cretaceous and Associated Mineralization)
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14 pages, 1716 KiB  
Article
Distribution of Trace Elements (Ag, Pd, Cd, and Mn) between Pyrite and Pyrrhotite and Selectivity of Surficial Nonautonomous Phases in a Hydrothermal System
by Sergey Lipko, Vladimir Tauson, Nikolay Smagunov, Dmitriy Babkin and Irina Parkhomenko
Minerals 2022, 12(9), 1165; https://doi.org/10.3390/min12091165 - 15 Sep 2022
Cited by 2 | Viewed by 1200
Abstract
The dual distribution coefficients (D) that are related to structurally and superficially bound trace element (TE) in pyrite (Py) and pyrrhotite (Po) associations, crystallized hydrothermally at 400 °C and 1 kbar pressure, were determined. Three independent methods were used to estimate [...] Read more.
The dual distribution coefficients (D) that are related to structurally and superficially bound trace element (TE) in pyrite (Py) and pyrrhotite (Po) associations, crystallized hydrothermally at 400 °C and 1 kbar pressure, were determined. Three independent methods were used to estimate the structural and surficial TE contents (Cstr and Csur) and the corresponding D Py/Po values (Dstr and Dsur), which were found, on average, to be 12.4, 0.8, 0.9, and 0.06 (Dstr) and 2.6, 0.7, 2.0, and 0.07 (Dsur) for Ag, Pd, Cd, and Mn, respectively. The coincidence of a dual D for several elements was a result of coupled changes in Csur and Cstr. The selectivity (S) of the surficial nonautonomous phases (NAPs) that were responsible for TE accumulation (which is the ratio of TE concentrations in surficial and structural modes) was determined. It was shown that the interpretation of TE uptake by surficial phases was adequate and that this phenomenon is common in nature, independently of the system where it occurs—i.e., in experimental autoclaves or in hydrothermal ore deposits. Studies of NAPs selectivity can help in evaluating the total element compatibility in minerals and the maximum possible contents of structurally bound admixtures of the element (solubility) in minerals under given conditions. A significant surficial impurity accumulation effect is most important and well-pronounced for incompatible micro-elements with concentrations of less than ~0.1 wt%. The surficial mode may be a source of Pd and other platinum group elements and more abundant and easily refined than the structurally bound mode. Full article
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13 pages, 3938 KiB  
Article
Experimental Study and Numerical Simulation on Dust Concentration Distribution of Chute at Enclosed Stockyard of Steel Works
by Hongtao Wang, Xuesong Wang, Shengfa Xia and Lei Li
Minerals 2022, 12(9), 1164; https://doi.org/10.3390/min12091164 - 15 Sep 2022
Cited by 1 | Viewed by 1041
Abstract
To clarify the dust concentration distribution of chute at the enclosed stockyard in steel works during the discharging process of materials, the experimental model based on the similarity principle was established in the laboratory, and the effects of the moisture content of materials, [...] Read more.
To clarify the dust concentration distribution of chute at the enclosed stockyard in steel works during the discharging process of materials, the experimental model based on the similarity principle was established in the laboratory, and the effects of the moisture content of materials, the height of chute, as well as the discharging amount of materials on the dust concentration of the selected four materials (MLG-S, ONM-N-F, MLC-N, and ONM-N) were experimentally investigated. Simultaneously, the dust concentration distribution and the motion trajectory of particles were numerically simulated by FLUENT software based on the gas-solid two-phase flow theory. The results showed that a large amount of dust are generated during the discharging process of materials at the enclosed stockyard, and the dust concentration is negatively depended on the moisture content of materials, while that is positively correlated with the height of chute. As the height of chute is increased from 2.2 m to 3.1 m, the concentration of dust generated by the MLG-S is accelerated from 7335.1 mg/m3 to 8881.1 mg/m3, and the concentration of dust produced by the ONM-N is increased from 1286.7 mg/m3 to 1964.3 mg/m3. Meanwhile, the higher dust concentration is from the materials with smaller particle sizes and more fine particles. Furthermore, the dust concentration in the chute space is gradually increased from the top to the bottom, and the bottom of the chute is the key area for controlling dust pollution. Full article
(This article belongs to the Topic Iron Concentrate Particles)
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26 pages, 7407 KiB  
Article
Late Cretaceous Activity Record of the Guangsan Fault—Insights from Zircon U-Pb and Apatite Fission-Track Thermochronology
by Ruxin Ding, Weihao Chen, Cleber Soares, Weisheng Hou, Zilong Li, Yangshijia Li, Rongli Huang and Heping Zou
Minerals 2022, 12(9), 1163; https://doi.org/10.3390/min12091163 - 14 Sep 2022
Cited by 1 | Viewed by 1181
Abstract
The timing of fault activity is a concern for geologists. This study used zircon U-Pb and apatite fission-track dating of fault breccia to determine the upper and lower limits for the time of faulting. The Guangsan fault in South China was taken as [...] Read more.
The timing of fault activity is a concern for geologists. This study used zircon U-Pb and apatite fission-track dating of fault breccia to determine the upper and lower limits for the time of faulting. The Guangsan fault in South China was taken as an example, and zircon U-Pb and apatite fission-track thermochronology were applied to the surrounding rock and fault breccia. The surrounding rock and fault breccia demonstrated 74.9–91.8 Ma and 73.9–93.5 Ma zircon U-Pb dates, respectively, indicating that the breccia formed after 73.9 Ma. They also demonstrated 71.6 ± 7.3 Ma and 85.9 ± 8.2–65.5 ± 6.5 Ma fission-track dates, implying that the fault breccia samples likely formed before ~70 Ma. Their thermal histories were highly consistent: both showed rapid cooling during 70–65 Ma and slow cooling during 65–0 Ma, implying that the fault was likely still active during 70–65 Ma, resulting in the rapid exhumation. Full article
(This article belongs to the Special Issue Fission Track Analysis and Its Application in Mineralogy)
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10 pages, 1777 KiB  
Article
Using Waste Brine from Desalination Plant as a Source of Industrial Water in Copper Mining Industry
by Constanza Cruz, Sebastián Herrera-León, Daniel Calisaya-Azpilcueta, Ruth Salazar, Luis A. Cisternas and Andrzej Kraslawski
Minerals 2022, 12(9), 1162; https://doi.org/10.3390/min12091162 - 14 Sep 2022
Cited by 5 | Viewed by 2219
Abstract
One of the main challenges of seawater desalination is a large volume of waste brine production that is commonly discharged into the sea and may threaten the marine ecosystem. This is critical in regions where conventional water resources are scarce and desalinated seawater [...] Read more.
One of the main challenges of seawater desalination is a large volume of waste brine production that is commonly discharged into the sea and may threaten the marine ecosystem. This is critical in regions where conventional water resources are scarce and desalinated seawater is an alternative to meet water demand. Especially in regions where the mining industry is a key player in the economic development. The novelty of this research consists in the determination of the potential use of waste brine, discharged from the reverse osmosis process, as a source of industrial water in copper mining industry. To enable the waste brine applicability, there should be reduced calcium and magnesium ions concentration for improving copper recovery in the froth flotation process. The flotation tests were conducted in a batch cell with synthetic minerals composed of chalcopyrite, kaolinite, and quartz using different water qualities. The results showed that treated waste brine significantly improved copper recovery compared to untreated waste brine and seawater. Similar copper recovery was achieved when flotation test was performed with tap water and treated waste brine. Therefore, treated waste brine could provide a suitable water quality required in the froth flotation process as an alternative non-conventional water resource. Full article
(This article belongs to the Special Issue Seawater Flotation)
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18 pages, 3881 KiB  
Article
Mineralogical and Geochemical Implications of Weathering Processes Responsible for Soil Generation in Mănăila Alpine Area (Tulgheş 3 Unit—Eastern Carpathians)
by Doina Smaranda Sirbu-Radasanu, Ramona Huzum, Delia-Georgeta Dumitraş and Cristina Oana Stan
Minerals 2022, 12(9), 1161; https://doi.org/10.3390/min12091161 - 14 Sep 2022
Cited by 2 | Viewed by 1796
Abstract
In the Mănăila alpine area, the soil layer developed in situ on top of the sericite-schists, which belong to the Tulghes 3 metamorphic unit. The aim of the present work was to determine the degree of soil formation using both mineralogical and geochemical [...] Read more.
In the Mănăila alpine area, the soil layer developed in situ on top of the sericite-schists, which belong to the Tulghes 3 metamorphic unit. The aim of the present work was to determine the degree of soil formation using both mineralogical and geochemical exploration methods. XRD, FTIR and SEM-EDS results showed that the soil constituents were dioctahedral 2:1 minerals, quartz, chlorite, Na-feldspar, rutire and ilmenite. Mainly illite and secondarily mixed-layer minerals were considered to be the most likely minerals resulting from the transformation of sericite and chlorite under acidic alpine conditions. Geochemical modeling inferred the dominance of illite and the presence of smectite as a chlorite alteration product. The weathering indices supported the moderate stage of the soil development agreeing with mineralogical observations. Because of the abundance of sericite and quartz in the parent material, the soil formation was retarded, and its present composition is still related to the bedrocks. Full article
(This article belongs to the Special Issue Soil Mineralogy on Ecosystem Functioning)
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15 pages, 2559 KiB  
Article
Stable Isotopic, Micro-FTIR, and Geochemical Characteristics of the Permian Madzaringwe Shale of Tuli Basin, South Africa: Implications for Organic-Rich Shale Provenance
by George Oluwole Akintola, Francis Amponsah-Dacosta, Steven Rupprecht and Sphiwe Emmanuel Mhlongo
Minerals 2022, 12(9), 1160; https://doi.org/10.3390/min12091160 - 14 Sep 2022
Viewed by 1545
Abstract
The paleo-environmental setting of an organic-rich shale remains an essential controlling factor for shale reservoir distribution. The scarcity of generalised data on paleo-environment settings has been spurred using a simple investigative approach to decipher the provenance of organic-rich shale in various regions. This [...] Read more.
The paleo-environmental setting of an organic-rich shale remains an essential controlling factor for shale reservoir distribution. The scarcity of generalised data on paleo-environment settings has been spurred using a simple investigative approach to decipher the provenance of organic-rich shale in various regions. This study investigates the organic-rich Madzaringwe shale of the Tuli Basin to reconstruct the provenance of the organic material for shale gas generation potential. Representative shale core samples were analysed for the stable isotopic fractions, functional groups, and major and trace compositions. The carbon isotopic composition, δ13C value, ranging from −21.01 to −24.0‰, averaging at −22.4‰. Inference from the stable isotopic compositions and functional group analysis indicate Type-III kerogen prone to gas generation in the studied Madzaringwe shale. The micro-Fourier transformed infrared (micro-FTIR) analysis reveals infrared absorption peaks between 2800 and 3300 cm−1 wavelengths corresponding to gaseous hydrocarbon. The x-ray fluorescence (XRF) result reveals major elements comprising Al2O3 (29.25–29.11%), CaO (0.29–0.28%), Fe2O3 (1.16–1.09%), K2O (0.97–0.98%), MgO (0.13–0.12%), Na2O (0.12–0.09%), P2O5 (0.22–0.21%), SiO2 (52.50–52.30%), and TiO2 (1.20–1.18%). The major element ratio of Al2O3/TiO2 values ≥ 25 indicates felsic and intermediate provenance from a terrigenous paleo-environment. In addition, laser ablation inductively coupled plasma mass spectrometry (LAICP-MS) reveals the trace elements in which elemental proxy of V/(V + Ni) with a value greater than 0.5 represent reducing environments. Furthermore, the geochemical proxies and isotopic compositions have revealed an anoxic paleo-environment for the non-marine-derived organic matter in the studied carbonaceous shale. Full article
(This article belongs to the Special Issue Reservoir and Geochemistry Characteristics of Black Shale)
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15 pages, 3387 KiB  
Article
On a Unified Core Characterization Methodology to Support the Systematic Assessment of Rare Earth Elements and Critical Minerals Bearing Unconventional Carbon Ores and Sedimentary Strata
by Scott N. Montross, Davin Bagdonas, Thomas Paronish, Andrew Bean, Andrew Gordon, C. Gabriel Creason, Burt Thomas, Erin Phillips, James Britton, Scott Quillian and Kelly Rose
Minerals 2022, 12(9), 1159; https://doi.org/10.3390/min12091159 - 14 Sep 2022
Cited by 2 | Viewed by 2167
Abstract
A significant gap exists in our understanding and ability to predict the spatial occurrence and extent of rare earth elements (REE) and certain critical minerals (CM) in sedimentary strata. This is largely due to a lack of existing, systematic, and well-distributed REE and [...] Read more.
A significant gap exists in our understanding and ability to predict the spatial occurrence and extent of rare earth elements (REE) and certain critical minerals (CM) in sedimentary strata. This is largely due to a lack of existing, systematic, and well-distributed REE and CM samples and analyses in United States sedimentary basins. In addition, the type of sampling and characterization performed to date has generally lacked the resolution and approach required to constrain geologic and geographic heterogeneities typical of subsurface, mineral resources. Here, we describe a robust and systematic method for collecting core scale characterization data that can be applied to studies on the contextual and spatial attributes, the geologic history, and lithostratigraphy of sedimentary basins. The methods were developed using drilled cores from coal bearing sedimentary strata in the Powder River Basin, Wyoming (PRB). The goal of this effort is to create a unified core characterization methodology to guide systematic collection of key data to achieve a foundation of spatially and geologically constrained REEs and CMs. This guidance covers a range of measurement types and methods that are each useful either individually or in combination to support characterization and delineation of REE and CM occurrences. The methods herein, whether used in part or in full, establish a framework to guide consistent acquisition of geological, geochemical, and geospatial datasets that are key to assessing and validating REE and CM occurrences from geologic sources to support future exploration, assessment, and techno-economic related models and analyses. Full article
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26 pages, 8709 KiB  
Article
Occurrence Characteristics of Magnetite and Aeromagnetic Prospecting Northeast of Hebei Province
by Yan-Xu Liu, Wen-Yong Li, Zhi-Yuan Liu, Jia-Wei Zhao, An-Qi Cao, Shan Gao, Li-Jie Wang and Cheng Yang
Minerals 2022, 12(9), 1158; https://doi.org/10.3390/min12091158 - 14 Sep 2022
Cited by 1 | Viewed by 1600
Abstract
The occurrence characteristics of magnetite and the methods to quickly and effectively explore are important topics for ore prospecting in the new era. Taking northeast of Hebei Province of China as an example, this article aimed at an important strategic mineral of magnetite, [...] Read more.
The occurrence characteristics of magnetite and the methods to quickly and effectively explore are important topics for ore prospecting in the new era. Taking northeast of Hebei Province of China as an example, this article aimed at an important strategic mineral of magnetite, then discussed its distribution characteristics and aeromagnetic exploration methods of it. First of all, we discuss the occurrence characteristics of sedimentary metamorphic and magmatic magnetite. Then, using the latest high-precision aeromagnetic data, combined with the geological outcrops, known iron deposits, ground magnetic surveys, and verification, we studied the relationship between the aeromagnetic anomalies and iron deposits through potential field conversion processing of the reduction to the pole, vertical derivative, upward continuation and residual anomaly, and the forward modeling and inversion methods of 2.5 D optimization fitting. Next, we summarize the metallogenic conditions and attributes of aeromagnetic prospecting and make magnetite predictions. In addition, it has suitable magnetite prospecting potential in the Laochenjia, Dabai, Jiuwuying, Beierying, Sidaogoumen, and Wuyingzi aeromagnetic anomaly regions. In conclusion, these regions have aeromagnetic anomalies with high amplitudes, large scales, and favorable metallogenic backgrounds for magmatic rocks, strata, and structures caused by concealed magnetite. In addition, they have great prospecting potential. Eventually, we hope this research method in this article can provide a reference for magnetite exploration in other areas with similar geological conditions. Full article
(This article belongs to the Special Issue Applications of Gravity and Magnetics to Mineral Exploration)
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21 pages, 4859 KiB  
Article
Genesis of Cambrian Dolomites in the Bachu Area, Tarim Basin, NW China: Constraints from Petrology, Geochemistry, and Fluid Inclusions
by Zhipeng Chen, Yanfei Yang, Caiyuan Dong, Ningxi Li, Pengtao Wang, Shaohua Zhang, Wei Dang and Yun Liao
Minerals 2022, 12(9), 1157; https://doi.org/10.3390/min12091157 - 14 Sep 2022
Cited by 1 | Viewed by 1311
Abstract
The dolomitization of carbonate rocks has always been a hot topic in the study of the dolomite reservoir. In this study, the genesis of Cambrian dolomite in the Bachu area, Tarim Basin, was assessed through petrographic examinations, isotope compositions (C, O, and Sr), [...] Read more.
The dolomitization of carbonate rocks has always been a hot topic in the study of the dolomite reservoir. In this study, the genesis of Cambrian dolomite in the Bachu area, Tarim Basin, was assessed through petrographic examinations, isotope compositions (C, O, and Sr), trace and rare earth elements, and fluid inclusion microthermometry. Microscopic analysis revealed three types of dolomites: very fine-crystalline, nonplanar dolomite (D1); fine-crystalline, nonplanar to planar-s dolomite (D2); and medium- to coarse-crystalline, planar-e to planar-s dolomite (D3). D1 dolomite exhibits well-preserved original sedimentary features, such as algal laminae, stromatolite, and evaporite streak, and is characterized by the 87Sr/86Sr value and δ18O value in equilibrium with the coeval seawater, its high Sr and Na content, and its low Mn content. This indicates that D1 dolomite is primarily a penecontemporaneous dolomite in tidal flat or lagoon environments, and its dolomitizing fluid is mainly evaporated mesosaline to penesaline seawater. D2 dolomite shows ghosts of precursor particles; features δ13C values in equilibrium with the coeval seawater, high 87Sr/86Sr values, low Sr content, and positive Eu anomaly; and is widely distributed close to stylolite. This illustrates that D2 dolomite was principally formed by seepage–reflux dolomitization, and is closely related to hydrothermal activity and pressure dissolution. D3 dolomite displays a crystal texture with a cloudy core and compositional zoning, and the original sedimentary fabrics cannot be identified. It has similar δ13C values and REE patterns to the calcite precipitated from coeval seawater, high 87Sr/86Sr values, low Sr contents and high Mn/Sr ratios, which suggests that D3 dolomite is chiefly related to the recrystallization of the precursor dolomite during the deep burial stage, and the deep circular brine provides Mg ions through the fluid–rock reaction. This study shows that the Cambrian dolomite in the Bachu area is mainly formed in the coeval seawater environment during the penecontemporaneous and shallow burial stages, and has extensively suffered from recrystallization and burial diagenesis due to long-term deep burial, which was further strengthened in the fracture-enriched area. Full article
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13 pages, 3701 KiB  
Article
On the Cobalt Content Upgrade in Nickeliferous Laterites Using Iron (III) Sulfate: A Study Based on Thermodynamics Simulations
by Rodrigo F. M. Souza, Mariana A. A. Tavares, Luiz E. C. Cruz, Víctor A. A. Oliveira, Iranildes D. Santos, Francisco J. Moura and Eduardo A. Brocchi
Minerals 2022, 12(9), 1156; https://doi.org/10.3390/min12091156 - 13 Sep 2022
Cited by 1 | Viewed by 1664
Abstract
Nickel (Ni) and cobalt (Co) are relevant technological metals for the future of the lithium-ion battery (LIB) industry. Based on the current and projected demand for these, an increased interest in developing processing routes to exploit lateritic occurrences has been observed, as these [...] Read more.
Nickel (Ni) and cobalt (Co) are relevant technological metals for the future of the lithium-ion battery (LIB) industry. Based on the current and projected demand for these, an increased interest in developing processing routes to exploit lateritic occurrences has been observed, as these are reported as critical raw materials for future mineral–metallurgical industry. However, the content of Ni and Co in such ores is minimal and requires impracticable mineral-processing operations for concentration before metal extraction. It was identified that information regarding the sulfation roasting of this material is scarce on what concerns the iron sulfates interaction as a function of the temperature. Based on that context, the present work has its purposes associated with the proposition of an alternative chemical pretreatment to upgrade the content of metals of technological interest in lateritic ores through a simple roast–leach process. Thus, the chemical interactions between the mineral sample and iron (III) sulfate (Fe2(SO4)3) through thermodynamic simulations and experimental procedures were explored. The latter included specific water leaching practices for the selective concentration of metals. The equilibrium calculations indicate that Fe2(SO4)3 and FeSO4 tend to decompose at lower temperatures, and considering the higher stability of other metal sulfates, it could be an interesting reagent in this type of process. Regarding the experimental results, the characterization of materials indicates a recovery of Co as high as 73.4 wt.% after sulfation roasting at 500 °C followed by water leaching, with the full content of Iron (Fe) being reported in the insoluble phase. Based on these findings, the present development could be an interesting alternative to consider within operations for the chemical upgrade of cobalt in such types of mineralogical occurrences. Full article
(This article belongs to the Special Issue Thermodynamics, Mechanism and Kinetics of Metallurgical Processes)
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13 pages, 4703 KiB  
Article
Subsidence Management and Prediction System: A Case Study in Potash Mining
by Nor Sidki-Rius, Lluís Sanmiquel, Marc Bascompta and David Parcerisa
Minerals 2022, 12(9), 1155; https://doi.org/10.3390/min12091155 - 13 Sep 2022
Cited by 10 | Viewed by 1668
Abstract
Subsidence is an important environmental and safety issue in the mining sector, yet there remain voids in knowledge in terms of management and prediction. This study aims to improve knowledge on the impact of mining operations on the surface, reducing their effect on [...] Read more.
Subsidence is an important environmental and safety issue in the mining sector, yet there remain voids in knowledge in terms of management and prediction. This study aims to improve knowledge on the impact of mining operations on the surface, reducing their effect on the environment, increasing the safety of mining operations, monitoring stress behavior and predicting rock mass. Therefore, an analysis was carried out to process and analyze the measured subsidence data and, subsequently, create a numerical model to predict the surface subsidence of a case study mine. The model was developed based on a finite element method (FEM). It was achieved by considering the geological characteristics of the area, the design features of the mine, the surface subsidence measured over twelve years and the time-dependent behavior of the geological layers. The correlation obtained between the measured subsidence and the modelling results was very satisfactory, with a 90% confidence level, over the years analyzed. Hence, the efficiency of the system was confirmed, enabling the evaluation and the prediction of potential surface effects, and therefore improving the safety and environmental levels of the mining area. Full article
(This article belongs to the Section Mineral Processing and Extractive Metallurgy)
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51 pages, 10601 KiB  
Review
Metalliferous Coals of Cretaceous Age: A Review
by Shifeng Dai, Sergey I. Arbuzov, Igor Yu. Chekryzhov, David French, Ian Feole, Bruce C. Folkedahl, Ian T. Graham, James C. Hower, Victor P. Nechaev, Nicola J. Wagner and Robert B. Finkelman
Minerals 2022, 12(9), 1154; https://doi.org/10.3390/min12091154 - 13 Sep 2022
Cited by 7 | Viewed by 4235
Abstract
Critical elements in coal and coal-bearing sequences (e.g., Li, Sc, V, Ga, Ge, Se, Y and rare earth elements, Zr, Nb, Au, Ag, platinum group elements, Re, and U) have attracted great attention because their concentrations in some cases may be comparable to [...] Read more.
Critical elements in coal and coal-bearing sequences (e.g., Li, Sc, V, Ga, Ge, Se, Y and rare earth elements, Zr, Nb, Au, Ag, platinum group elements, Re, and U) have attracted great attention because their concentrations in some cases may be comparable to those of conventional ore deposits. The enrichment of critical elements in coals, particularly those of Carboniferous-Permian and Cenozoic ages, have generally been attributed to within-plate (plume-related) volcanism and associated hydrothermal activity. However, Cretaceous coals are not commonly rich in critical elements, with the exception of some (e.g., Ge and U) in localised areas. This paper globally reviewed metalliferous coals from Siberia, the Russian Far East, Mongolia, South America, the United States and Mexico, Canada (Alberta and British Columbia), China, Africa, and Australasia (Victoria, Queensland, New South Wales, South Australia, Northern Territory, New Zealand, Nelson, West Coast, Canterbury, Otago, and Southland). The world-class Ge-U or Ge deposits in North China, Mongolia, and Siberia are the only commercially significant representatives of the Cretaceous metalliferous coals, which are related to bio-chemical reduction of oxidized meteoric, hydrothermal, or sea waters by organic matter of the peat bogs. The common Cretaceous coals worldwide are generally not rich in critical elements because intensive igneous activity led to extensive acidification of terrestrial and marine waters, which are responsible for the low coal metallogenesis during the Cretaceous period, especially the Early Cretaceous time. Full article
(This article belongs to the Special Issue Geological Evolution of The Cretaceous and Associated Mineralization)
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33 pages, 23991 KiB  
Article
Mineralogical Properties of the Copper Slags from the SarCheshmeh Smelter Plant, Iran, in View of Value Recovery
by Saeed Mohamadi Nasab, Behnam Shafiei Bafti, Mohamad Reza Yarahmadi, Mohammad Mahmoudi Maymand and Javad Kamalabadi Khorasani
Minerals 2022, 12(9), 1153; https://doi.org/10.3390/min12091153 - 12 Sep 2022
Cited by 4 | Viewed by 2286
Abstract
Annually, hundreds of thousands of tons of slags are involved in the reverberator and flash smelting as well as converting operations of Cu-Fe sulfide concentrates to produce matte in the Sar Cheshmeh copper smelter plant, Iran, disposed in the landfill and cooled in [...] Read more.
Annually, hundreds of thousands of tons of slags are involved in the reverberator and flash smelting as well as converting operations of Cu-Fe sulfide concentrates to produce matte in the Sar Cheshmeh copper smelter plant, Iran, disposed in the landfill and cooled in air. Due to their relatively high average copper content (about 1.5 wt%), a mineral processing plant based on the flotation process has recently been established to produce thousands of tons of Cu-sulfide concentrate after slag crushing and fine grinding operation. In order to make the flotation process more efficient, more knowledge is required on the form and origin of the copper losses in the slag. To achieve this, mineralogical studies of the slags using optical microscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM) methods have been carried out. Mineralogical analyses showed the main part of copper losses into the semi- to fully-crystallized magnetite-rich reverberator and flash slags characterized by crystal–glass matrix ratio ≤ 1 is moderate to coarse particles of Cu-Fe sulfides, i.e., chalcopyrite (CuFeS2) and bornite (Cu5FeS4), that are mainly chemically entrapped. In contrast, the mechanically entrapped fine- to coarse-grain (from 20 up to 200 µm) spherical-shaped of high-grade matte particles with chalcocite (Cu2S) composition containing droplets or veinlets of metallic copper (Cu0) are the dominant forms of copper losses into the converter slags characterized by crystal–glass matrix ratio > 1. From the value recovery point of view, our result show that the fully crystallized slags containing moderate- to coarse-grain copper-bearing particles will result in efficient recovery of a significant amount of entrained copper due to better milling response compared to semi-crystallized ones due to locking the fine- to moderate-grain copper particles in the silicate glassy matrix. Laboratory-scale grinding experiments showed that normal (≤74 μm) to fine (≤44 μm) grinding of high- Cu grade slags lead to a significant increase in the liberation degree of copper particles. in contrast, the increase in fine particle fractions (<37 μm) due to re-grinding or ultra-fine grinding of the originally low-Cu grade slags does not lead to the liberation of copper particles, but it will reduce the efficiency of the flotation process. This study suggests that the highest rate of copper recovery of the slag by the flotation process will be obtained at particle size 80% passing 44 µm which has also reached the optimal liberation degree of copper-bearing particles. Full article
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23 pages, 10389 KiB  
Article
Mineral Chemistry of the Lower Cretaceous Jinling Iron Skarn Deposit, Western Shandong Province, North China Craton: Implications for the Iron Skarn Mineralization Process
by Fang-Hua Cui, Chao Zhang, Dai-Tian Jin, Lu-Yuan Wang, Ji-Lei Gao, Ming Ma and Ya-Dong Li
Minerals 2022, 12(9), 1152; https://doi.org/10.3390/min12091152 - 12 Sep 2022
Cited by 1 | Viewed by 1781
Abstract
The source of iron material and the mineralization process of iron skarn deposits within the eastern North China Craton are ambiguous. In this study, we present new mineral chemical data of the Jinling skarn deposit, located in western Shandong Province, east China. Based [...] Read more.
The source of iron material and the mineralization process of iron skarn deposits within the eastern North China Craton are ambiguous. In this study, we present new mineral chemical data of the Jinling skarn deposit, located in western Shandong Province, east China. Based on the petrography study and mineral chemical data, we suggest that the Jinling iron skarn deposit is hydrothermal and the metallogenic iron is enriched by leaching of Fe-rich fluids derived from primitive magmatic melt from the solidified diorites. The Jinling iron skarn deposit formed as a result of several mineralization processes: (1) Fe-rich hydrothermal fluids exsolved from a hydrous parental magma that was characterized by high iron content, oxygen fugacity (fO2), and salinity; (2) the Fe content of the fluids was augmented during the alkali metasomatism stage via the leaching of Fe from the solidified dioritic rocks; (3) diopside and garnet in skarns formed under relatively alkaline and oxidizing conditions during the later prograde skarn stage; (4) during the retrograde skarn stage, amphibole, chlorite, epidote, phlogopite, serpentine, biotite, and chlorite formed under more oxidizing conditions, and subsequent mixing of the Fe-rich fluids with meteoric water triggered the precipitation of the massive magnetite; and (5) the final sulfide–carbonate stage was involved in the formation of carbonate and sulfide minerals as a result of a change in conditions from oxidizing to reducing. Full article
(This article belongs to the Special Issue Mineral Resources in North China Craton)
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17 pages, 9106 KiB  
Article
Unravelling the Temporal and Chemical Evolution of a Mineralizing Fluid in Karst-Hosted Deposits: A Record from Goethite in the High Atlas Foreland (Morocco)
by Michèle Verhaert, Cécile Gautheron, Augustin Dekoninck, Torsten Vennemann, Rosella Pinna-Jamme, Abdellah Mouttaqi and Johan Yans
Minerals 2022, 12(9), 1151; https://doi.org/10.3390/min12091151 - 11 Sep 2022
Cited by 1 | Viewed by 1488
Abstract
Timing and duration of ore deposit formation are crucial to understanding the mineralization process. To address this, the geochronological (U-Th)/He method, geochemical and H- and O-isotope compositions of pure goethite formed in the Imini karst-hosted Mn district (High Atlas, Morocco) were examined in [...] Read more.
Timing and duration of ore deposit formation are crucial to understanding the mineralization process. To address this, the geochronological (U-Th)/He method, geochemical and H- and O-isotope compositions of pure goethite formed in the Imini karst-hosted Mn district (High Atlas, Morocco) were examined in detail. Two main generations of cavity-filling and fracture-filling goethite are identified, and both precipitated prior to the massive Mn oxide ore. The δD and δ18O values reveal that the mineralizing fluid of cavity and fracture-filling goethite is meteoric-derived but enriched in 18O due to fluid–rock interactions with the host rock dolostone or mixing with O2-rich surface water resident in an open karst system. The cavity-filling goethite precipitated between 95 to 80 Ma, whereas fracture-filling goethite formed between 80 to 50 Ma. Ore deposition occurred discontinuously during the early Atlas doming associated with one or more early compressional events in the Atlas tectonism. The increase in δD values and depletion in U content result from a change in the mineralizing fluid within the karst system. At about 50 Ma, the fluid is notably enriched in U, Cu and trace metals. Full article
(This article belongs to the Special Issue Mineralogy of the Supergene Zone)
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11 pages, 4515 KiB  
Review
Phanerozoic Evolution of Continental Large Igneous Provinces: Implications for Galactic Seasonality
by Victor P. Nechaev, Frederick L. Sutherland and Eugenia V. Nechaeva
Minerals 2022, 12(9), 1150; https://doi.org/10.3390/min12091150 - 11 Sep 2022
Cited by 1 | Viewed by 1333
Abstract
This study reviews the available data on the Phanerozoic plume activity (Large Igneous Provinces (LIP’s) size and frequency) and geochemistry of their igneous rocks. A major goal of this review is to try to find the changes in intensity and geochemistry of mantle [...] Read more.
This study reviews the available data on the Phanerozoic plume activity (Large Igneous Provinces (LIP’s) size and frequency) and geochemistry of their igneous rocks. A major goal of this review is to try to find the changes in intensity and geochemistry of mantle plumes linked to the Earth’s evolution and galactic seasonality that was supposed in the authors’ previous publications. The data indicate that the Cambrian–Ordovician and Jurassic–Cretaceous galactic summers were associated with peaks of various igneous activities including both plume- and subduction/collision-related magmatism, while the Carboniferous–Permian and current galactic winters led to significant drops within the igneous activity. The materials subducted into the transitional and lower mantle, which highly influenced the plume magmas in the galactic-summer times, were less significant in the galactic spring and autumn seasons. The least subduction-influenced LIPs were probably the Tarim and Emeishan deep plume magmas that developed in the mid–late Permian, during the galactic late winter–early spring subseason. The Fe enrichment of clinopyroxenite, gabbro, and associated ores of these provinces might be caused by fluids ascending from the core–mantle boundary. However, the most significant core influence through plume-associated fluids on the surface of solid Earth is supposed to have occurred in the galactic summer times (Cambrian–Ordovician and Jurassic–Cretaceous), which is indicated by peak abundances of ironstone ores. Their contributions to the Cambrian–Ordovician and Jurassic–Cretaceous plume magmas were, however, obscured by more significant influences from subduction. Full article
(This article belongs to the Special Issue Geological Evolution of The Cretaceous and Associated Mineralization)
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