Vanadium Deposits Research Articles

Mannardite as the main vanadium-hosting mineral in black shale-hosted vanadium deposits, South China

Abstract Black shale-hosted vanadium (V) deposits account for about 80% vanadium resources in the world, but only <2% vanadium in the black shale can be extracted mainly due to insufficient recognition on the occurrence mode of vanadium. It is commonly agreed that most vanadium in the black shale is hosted in clay minerals and organic matters, but it is not clear how the other parts of vanadium exist and whether there exists a vanadium mineral, which has limited our understanding of metallogenic mechanism of black shale-hosted vanadium deposits. The Jiujiang Basin at the Lower Yangtze Block is a significant black shale-hosted vanadium metallogenic district. In this work, we conducted systematic studies of mineralogy, lithology and geochemistry on the occurrence of vanadium hosted in the black shales. Electron probe microanalysis (EPMA), Raman spectroscopy, and X-ray diffraction (XRD) show that the main vanadium-hosting mineral in the black shale is mannardite, with a structural formula of [Ba0.96∙H2O](Ti5.87V1.873+V0.114+Si0.07Cr0.07Fe0.023+)O16.00, space group I41/a, unit-cell parameters a = b = 14.346(7) Å, c = 5.899(1) Å, α = β = γ = 90°, Z = 4. Data from EPMA, TESCAN integrated mineral analyzer (TIMA), and whole-rock geochemistry indicate that 12.32–44.06% (average 24.95%) vanadium exists in mannardite. Most vanadium atoms in mannardite occupy its structural sites as trivalent vanadium (V3+), forming chemical bonds with O atoms as VO2−, whereas a minor amount of vanadium atoms replace titanite atoms (Ti4+) as quadrivalent vanadium (V4+) by isomorphism. Mannardite precipitates under a strong reductive condition with sufficient trivalent vanadium species, titanium and biogenic barium (bio-barite). Our first identification of mannardite in black shale-hosted vanadium deposits thus sheds light on the occurrence mode of vanadium and the metallogenic mechanism of black shale-hosted vanadium deposits.

Mineralogy and trace element geochemistry of the early Cambrian black shale-hosted Zhongcun vanadium deposit, southern Qinling, China

Mineralogy and trace element geochemistry of the early Cambrian black shale-hosted Zhongcun vanadium deposit, southern Qinling, China

Application of principal component analysis and a spectrum-area fractal model to identify geochemical anomalies associated with vanadium mineralization in northeastern Jiangxi Province, South China

The Jiujiang region in northeastern Jiangxi Province is known for hosting many black shale-type vanadium deposits, which are mainly found in the Cambrian Hetang Formation and Sinian Piyuancun Formation. In this paper, based on stream sediment data, principal component analysis (PCA) and spectrum–area (S–A) fractal modelling are used to identify geochemical anomalies associated with vanadium (V) mineralization. First, a dataset containing 957 samples of stream sediments with 39 elements was processed using correlation analysis and cluster analysis to find the closest V-related elements, and Ag and Cd were obtained. Secondly, the raster maps of V, Ag and Cd were created using multifractal inverse distance-weighted interpolation. PCA was then employed to combine the concentration values of V, Ag and Cd into a single variable representing the internal relationships among the three elements. Finally, S–A analysis was used to decompose the first component pattern obtained through PCA and to extract anomalies from the complex background. The results show that the known V deposits are located within highly anomalous areas, which are well corelated with the distribution of black shales of the Hetang and Piyuancun Formations. It is suggested that the northeastern part of Jiangxi Province potentially hosts undiscovered V deposits, and the identified anomalies could be further used to guide mineral exploration.Thematic collection:This article is part of the Applications of Innovations in Geochemical Data Analysis collection available at:https://www.lyellcollection.org/cc/applications-of-innovations-in-geochemical-data-analysis

Mineral–Geochemical Features of Paleoproterozoic Gold–Copper–Sulfide, Noble Metal-Copper–Uranium, and Noble-Metal–Copper–Uranium–Vanadium Deposits and Ore Occurrences of Karelia

Mineral–Geochemical Features of Paleoproterozoic Gold–Copper–Sulfide, Noble Metal-Copper–Uranium, and Noble-Metal–Copper–Uranium–Vanadium Deposits and Ore Occurrences of Karelia

Study on Occurrence and Optionality of Vanadium in Bauxite-type Vanadium Deposits, Northern Sichuan.

Study on Occurrence and Optionality of Vanadium in Bauxite-type Vanadium Deposits, Northern Sichuan.

Establishment of geochemical thresholds for vanadium throughout Korea and at potential development sites using geochemical map data.

Geochemical maps can be used for a variety of purposes, one of which is to establish regional or local geochemical thresholds for the analyzed elements. In the case of vanadium, as industrial demand and use increase, it is necessary to expand the development of vanadium in Korea. However, the environmental management standards are insufficient. Therefore, in this study, using geochemical data, we derived geochemical threshold values for the entire country and areas with potential for the development of vanadium deposits. The regional (country-wide) threshold value was derived using logarithmic transformation of raw data (N = 23,548) of the first- and second-order stream sediments collected across the country in the late 1990s and the early 2000s. The median + 2 median absolute deviation (MAD) and Tukey inner fence (TIF) values were 116mg/kg and 200mg/kg, respectively. Of these, the TIF standard, which showed 0.6% of data exceeding the threshold, was judged to be appropriate for distinguishing clear enrichment or contamination of vanadium. In the case of the Geumsan and Pocheon, areas with potential for vanadium development, the TIF and median + 2 MAD values of 259mg/kg and 218mg/kg, respectively, can be used as the criteria for evaluating the impact of environmental pollution before and after deposit development. Likewise, by deriving threshold values of the target elements using geochemical map data, it is possible to provide basic environmental information for geochemical evaluation and follow-up management in advance during large-scale site development.

AN INNOVATIVE METHOD FOR PROCESSING OF USED VANADIUM CATALYSTS FOR OBTAINING VANADIUM PENTOXIDE

All in all, there are about 60 million vanadium deposits in the world, 90% of which are localized in the territory of the five countries: Russia, South Africa, Venezuela, the United States and China. Sulfuric acid production is the main consumer of vanadium in the form of vanadium catalysts (V2 O5 pentoxide). The demand for vanadium and its compounds keeps growing every year, as a result of the increased interest in processing of secondary vanadium-containing raw materials. One of the main sources of vanadium are the spent vanadium catalysts – SVC. About 100 thousand tons of spent vanadium catalysts are formed throughout the country, which are considered to be potentially hazardous for the environment and local population. Disposal of spent vanadium catalysts used for oxidizing of sulfur dioxide represents a serious environmental threat due to the lack of effective technologies for their processing. This work is devoted to a method for processing of spent vanadium catalysts to obtain a stuff that will be suitable for modifying of steels. The pyrometallurgical method of processing of technogenic raw materials by oxidative fi ring has been investigated and the parameters of firing – optimal fi ring time and temperature for extracting vanadium from the material – have been identified.

Origin and Enrichment of Vanadium in the Lower Cambrian Black Shales, South China.

The Lower Cambrian black shales of the Sansui vanadium deposits, located in South China, host a thin accumulation of Ni, Mo, V, and platinum group of elements (PGE). However, among them, the origin of V-bearing deposits remains controversial. To characterize the enrichment process of V-bearing deposits, samples of the mineralized layer and surrounding rocks from the Sansui area, South China, were investigated through bulk geochemical analysis and scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) analyses. There is a consistency in the change curves of Mo, Ni, and V from the Sansui V deposits, but the contents of elements show a great difference. This means the strong similarities in the metal sources but a difference in enrichment factors of Mo, Ni, and V. The presence of the tuff and the barite layer in the Sansui V deposits indicates that the formation of the associated V deposits was closely related to either a volcanic or hydrothermal activity. Analysis of geochemistry and sedimentation suggests a hydrothermal source of the metals, where the mineralization of V is related to clay and organic matter. Phosphorus nodules were observed at all sites of black shale V deposits in early Cambrian and were most likely related to the upwelling currents during the depositional period. The comparison with the Ni–Mo deposits highlights a stronger enrichment of clay in the V deposits. The V deposits are located in the lower part of the continental slope. Both organic matter and clay minerals are abundant in the Sansui deposits. However, the isomorphism of V–Al is promoted by the hydrothermal activity and suggests that the origin of V deposits is a multistage process.

Age of the lower Cambrian Vanadium deposit, East Guizhou, South China: Evidences from age of tuff and carbon isotope analysis along the Bagong section

Abstract The early Cambrian is a critical interval of dramatic oceanic and biochemical changes in geological history. The black shale deposits, which are rich in Mo, Ni, V, and platinum group elements (PGE), are a reflection of that interval. Among all known Cambrian black shale deposits in South China, the vanadium deposits are poorly constrained by geochronology. The newly discovered tuff layer in the Sansui Bagong vanadium deposit in Guizhou Province can provide excellent constraints on the age of vanadium deposits. In this study, we obtain a new zircon U–Pb isotopic age, which can constrain the age of the vanadium deposit. This tuff occurs in the middle part of the ore bed, and the age of the tuff layer can reflect the mineralization age of the V deposit. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is used in this study to obtain the zircon U–Pb age of the tuff and indicates that the event of volcanic activity took place at 520.9 ± 1 Ma. This age is close to the boundary between the Cambrian Terreneuvian and Series 2. This result provides a good constraint on the age of the vanadium deposits in South China and makes the vanadium deposits to be comparable with other Mo–Ni–PGE deposits. The alteration of organic carbon isotope (δ 13Corg) values can reflect changes in the marine environment and is widely used in stratigraphic correlation. The analysis of the δ 13Corg values of the ore bed in the present study reveals a positive excursion at the bottom of the deposit and a negative excursion in the V-enriched layer. The δ 13Corg values in the Bagong section are comparable to those in the Xiaotan and Longbizui sections. The ages of the Sansui vanadium deposit constrained by the U–Pb isotopic age of the tuff and the δ 13Corg values are consistent. All of the data lead us to infer that the vanadium deposit formed at approximately 521 Ma.

Efficient separation of black shale-hosted vanadium induced by formation of kalunite-jarosite solid solution in two-stage pressurized acid leaching coupled with lixivium recycling

Black shale-hosted vanadium deposit is an important species of nontraditional mineral resources. The green efficient separation of black shale-hosted vanadium has attracted lots of researchers’ attention. In the paper, two-stage pressurized acid leaching coupled with lixivium recycling was investigated and clarified. Results showed that this coupling technics endowed selective leaching of vanadium under the optimized conditions that were liquid to solid ratio of 1.5 mL/g, leaching time of 120 min, sulfuric acid addition of 12.5 vol%, the first-stage temperature of 180 °C and second-stage temperature of 150 °C. From the first stage to the second stage, the muscovite has been almost dissolved, which guaranteed high vanadium recovery. Through recycling the second-stage lixivium, the first-stage pH value was controlled below pHTθ of Eq. (5) (0.27, 180 °C) and above pHTθ of Eq. (6) (−0.88, 180 °C) and Eq. (7) (−2.83, 180 °C), triggering the isomorphous precipitation of Fe and Al as kalunite-jarosite solid solution. Once fresh sulfuric acid solution touched the first-stage residue, the kalunite-jarosite solid solution can still be stably remained and discharged. The leached Fe and Al ions were directionally gathered to the first stage and precipitated as kalunite-jarosite solid solution. Recent data collected from this coupling technics suggests that the asynchronous dissolution-precipitation of V, Al and Fe was achieved during acid leaching of the black shale.

Dating the Bushveld Complex: Timing of Crystallization, Duration of Magmatism, and Cooling of the World’s Largest Layered Intrusion and Related Rocks

Abstract The Paleoproterozoic Bushveld Complex, including the world’s largest layered intrusion and host to world-class stratiform chromium, platinum group element, and vanadium deposits, is a remarkable natural laboratory for investigating the timescales of magmatic processes in the Earth’s crust. A framework for the emplacement, crystallization, and cooling of the Bushveld Complex based on integrated U–Pb zircon–baddeleyite–titanite–rutile geochronology is presented for samples of different rock types from the Bushveld Complex, including ultramafic and mafic cumulates, mineralized horizons, granitic rocks from the roof, and a carbonatite from the nearby alkaline Phalaborwa Complex. The results indicate that (1) the Bushveld Complex was built incrementally over an ∼5 Myr interval from 2060 to 2055 Ma with a peak in magma flux at c. 2055–2056 Ma, (2) U–Pb zircon crystallization ages do not decrease in an uninterrupted systematic manner from the base to the top of the intrusion, indicating that the Bushveld Complex does not represent the crystallized products of a single progressively filled and cooled magma chamber, and (3) U–Pb rutile dates constrain cooling of the intrusion at the level of the Critical Zone through ∼500 °C by 2053 Ma. The c. 2060 Ma Phalaborwa Complex (pyroxenite, syenite, carbonatite + Cu–Fe-phosphate–vermiculite deposits) represents one of the earliest manifestations of widespread Bushveld-related magmatism in the northern Kaapvaal craton. The extended range and out-of-sequence U–Pb zircon dates determined for a harzburgite from the Lower Zone (c. 2056 Ma), an orthopyroxenite from the Lower Critical Zone (c. 2057 Ma), and orthopyroxenites from the Upper Critical Zone (c. 2057–2060 Ma) are interpreted to indicate that the lower part of the Bushveld Complex developed through successive intrusions and accretion of sheet-like intrusions (sills), some intruded at different stratigraphic levels. Crystallization of the main volume of the Bushveld Complex, as represented by the thick gabbroic sequences of the Main Zone and Upper Zone, is constrained to a relatively narrow interval of time (∼1 Myr) at c. 2055–2056 Ma. Granites and granophyres in the roof, and a diorite in the uppermost Upper Zone, constitute the youngest igneous activity in the Bushveld Complex at c. 2055 Ma. Collectively, these results contribute to an emerging paradigm shift for the assembly of some ultramafic–mafic magmatic systems from the conventional ‘big tank’ model to an ‘amalgamated sill’ model. The volume–duration relationship determined for magmatism in the Bushveld Complex, when compared with timescales established for the assembly of other layered intrusions and more silica-rich plutonic–volcanic systems worldwide, is distinct and equivalent to those determined for Phanerozoic continental and oceanic flood basalts that constitute large igneous provinces. Emplacement of the 2055–2060 Ma Bushveld Complex corresponds to the end of the Lomagundi–Jatuli Event, the largest magnitude positive carbon isotope excursion in Earth history, and this temporal correlation suggests that there may have been a contribution from voluminous Bushveld ultramafic–mafic–silicic magmatism to disruptions in the global paleoenvironment.

A Review on Types of Vanadium Deposits and Process Mineralogical Characteristics

A Review on Types of Vanadium Deposits and Process Mineralogical Characteristics

Chromium-rich vanadio-oxy-dravite from the Tzarevskoye uranium–vanadium deposit, Karelia, Russia: a second world-occurrence of Al–Cr–V–oxy-tourmaline

AbstractA green tourmaline sample from the Tzarevskoye uranium–vanadium deposit, close to the Srednyaya Padma deposit, Lake Onega, Karelia Republic, Russia, has been found to be the second world-occurrence of Cr-rich vanadio-oxy-dravite in addition to the Pereval marble quarry, Sludyanka crystalline complex, Lake Baikal, Russia, type-locality. From the crystal-structure refinement and chemical analysis, the following empirical formula is proposed: X(Na0.96K0.02□0.02)Σ1.00Y(V1.34Al0.68Mg0.93Cu2+0.02Zn0.01Ti0.01)Σ3.00Z(Al3.19Cr1.36V0.03Mg1.42)Σ6.00(TSi6O18)(BBO3)3V(OH)3W[O0.60(OH)0.23F0.17]Σ1.00. Together with the data from the literature, a compositional overview of Al–V–Cr–Fe3+-tourmalines is provided by using [6]Al–V–Cr–Fe3+ diagrams for tourmaline classification. These diagrams further simplify the tourmaline nomenclature as they merge the chemical information over the octahedrally-coordinated sites (Y and Z) by removing the issues of uncertainty associated with cation order–disorder across Y and Z. Results show the direct identification of tourmalines by using the chemical data alone.

The Bigrlyi Tabular Sandstone-Hosted Uranium–Vanadium Deposit, Ngalia Basin, Central Australia

The Bigrlyi deposit is a tabular, sandstone-hosted, uranium–vanadium deposit of Carboniferous age located in the Ngalia Basin of central Australia. The deposit is similar to the continental, fluvial Saltwash-type of sandstone-hosted U-V deposits which are well known from the Colorado Plateau, USA. Most mineralization at Bigrlyi occurs as thin, multiple-stacked, stratiform lenses at the base of fluvial channels near the contact between a grey sandstone succession and a hematitic, purple–red sandstone succession. A larger halo of lower grade vanadium mineralization extends beyond the main U-V-mineralized zone. The host is an immature, feldspathic sandstone, grading into arkose and lithic-rich variants. Lithic ‘rip-up’ clasts of clay-rich sediments are common in the basal parts of fluvial channels, and are frequently the focus of, and have acted as sites for, U-V mineralization. Coffinite and uraninite are the main uranium minerals, with the former dominant. Vanadium is mainly hosted by Fe-V-bearing clays and chlorite, including roscoelite, grading into vanadian illite, the interlayer mineral corrensite, and altered detrital biotite. The V-Fe–oxyhydroxide minerals montroseite, haggite and doloresite, and altered detrital Fe-Ti oxides, are minor V-hosts. Mineralized zones correlate with enrichments in Se, Li, Ba, Be, Mo, Mg and Fe, and elevated Se/S ratios are characteristic of U-mineralized zones. Petrographic studies show that a heterogeneous mixture of variably mineralized lithic clasts is present; in the same rock, some clasts are Fe-rich and only weakly U-V-mineralized, while other clasts are strongly V- and/or U-mineralized. These observations point to mineralization processes that did not take place in-situ in the host sandstone at the site of deposition as required by conventional groundwater models. Lead isotope results provide evidence of the open-system mobility of radiogenic elements in parts of the deposit. In V-bearing zones, radiogenic Pb contents were found to be unsupported by current U levels, suggesting that over time U has been mobilized from these zones and redistributed, resulting in U-enrichment in other parts of the deposit. Mobility pathways were likely open over time from early in the history of the Bigrlyi deposit. A hybrid mineralization model, involving an interplay between solution-precipitation processes, detrital transport and post-depositional U remobilization, is proposed for Bigrlyi. Ferrous-ion-bearing clay minerals and pyrite are considered to be the most likely primary reductants/adsorbents, while the deposit is lacking carbonaceous matter.

Vanadium in the Arctic zone of Russia on the Kola region example: prevalence, sources, industrial potential

This article gives a brief overview of the prevalence, sources and industrial potential of vanadium in the Arctic zone of Russia on the Kola region example. Within the Kola region many solid minerals is mining: apatite-nepheline ores of the Khibiny, rare earth elements ore of Lovozero, baddeleyite-apatite-magnetite ores of the Kovdor, ferruginous quartzites of Olenegorsk, copper-nickel deposits of Pechenga etc. In the region potential deposits of platinum group elements, chromium, titanium, lithium and beryllium are explored. Recent studies conducted by the workers of the KSC RAS, in combination with geological and exploration data of predecessors, indicate that within the Kola region there are large sources of vanadium. Numerous occurrences of vanadium mineralization, as well as deposits of vanadium, are mainly localized within the entire Paleoproterozoic Pechenga-Imandra-Varzuga (PIV) rift belt, which stretches for more than 500 km across the entire Kola Peninsula - from the throat of the White sea in the North-East to the Norwegian Caledonian in the North-West. The time of the belt development is considered to be at the period 2.5-1.7 Ga. Elevated concentrations of vanadium is installed in metasomatites at the contact of volcanics and dolomite in Prikhibin’e, in sedimentary rocks of the North Pechenga area and throughout the black-shale strata of the entire PIV zone. Mineralization, composed by extremely rare vanadium minerals, established in massive sulfide ores of the PIV belt, however, has only scientific interest. Potential sources of industrial extraction of vanadium are complex Fe-Ti-V ores, which are components of mafic/ultramafic layered intrusions. The study of Fe-Ti-V ores of the region continues.

Experimental investigations of vanadium and nickel distribution while firing petcoke in a circulating fluidised bed test facility

Petcoke was fired as independent fuel in CFB test facility and the distribution of vanadium and nickel throughout the boiler and its deposition rate was assessed. It was found out that during combustion, 7%-8% of the total vanadium is in bottom zone of furnace, 31%-33% is in circulating zone, nearly half of total V (47%-49%) is in second pass and the rest 11%-15% got deposited in the boiler or escaped through the stack. Meanwhile in the case of nickel, 26%-29% is in primary loop and rest 66%-68% is in second pass. Vanadium deposits were found as inclusions in lime based deposits. XRF and XRD analysis of loose deposits found in back pass confirms the presence of vanadium. It was noticed that although petcoke contains high amount of vanadium and nickel, most of them were absorbed in situ limestone and turned to stable solid form. [Received: February 1, 2017; Accepted: July 6, 2017]

Efficient extraction and separation of vanadium and chromium in high chromium vanadium slag by sodium salt roasting-(NH4)2SO4 leaching

A novelty process based on sodium salt roasting-(NH4)2SO4 leaching was proposed to extract vanadium and chromium in high chromium vanadium slag (HCVS). V2O5 and Cr2O3 was then prepared. The effects of roasting and leaching conditions on vanadium and chromium extraction behavior were studied systematically and completely. Vanadium precipitation conditions and chromium reduction conditions were optimized further. 94.6% vanadium and 96.5% chromium were extracted when HCVS and Na2CO3 were mixed in the molar ratio of n(Na2CO3)/n(V2O3+Cr2O3) of 2.5, then leached in 30g/L (NH4)2SO4 solution. 94.8% vanadium was precipitated as ammonium polyvanadate (APV) just by adjusting the leaching liquid pH at 4.5, almost all chromium was remained in liquid, achieving the efficient separation of vanadium and chromium. Chromium was then recovered by reduction and precipitation. More than 99% chromium was reduced when Na2S2O5 was added in m(Na2S2O5)/m[Cr(VI)] above 3. By roasting the deposits of vanadium and chromium respectively, 91.49% V2O5 and 89.89% Cr2O3 were obtained. The supernatant after vanadium and chromium extraction containing NH4+ could be recycled as the new leaching medium with some new (NH4)2SO4 added, which greatly reduced the discharge of ammonia-nitrogen wastewater and made the whole process more environmentally friendly.

Перспективы золотоносности докембрийских комплексов Приполярного Урала

Precambrian strata - the most important source of many types of mineral raw materials. Within their boundaries are the largest deposits of iron, gold, chromium, diamonds, platinoids, nickel, copper, polymetals, vanadium and uranium. Consequently, they can be considered as the most promising provinces for the discovery of new large deposits. The authors briefly described the gold mineralization of the Urals, which are distributed unevenly and mainly among Paleozoic formations. It is noted that common features to all these objects is their location to the east of the Main Ural Foult (GUR - in Russian), and in the North, Subpolar and PolarUrals Mountains, west of the GUR, on the Precambrian development area of the Cent­ral Ural Uplift, manifestations of indigenous gold are still rare. The authors cite the results of geological exploration for ore gold within the Khobeiz “dome”, at a very promising Halmerinsky ore-placer site, where the Sosnovoye, Talayiz and Vorgavozh deposits were discovered. These deposits are confined to the Omras'shorian fault system, which is traced more than 25 km along a strike across the whole area, and the width of the development of individual structures is 4 km. At the Sosnovoe deposit, ore bodies are located within a block about 140 m wide and 240-250 m long, bounded by the West and East faults of the north-eastern strike, steeply falling to the west, and the shallow zones of melanocratic blastomylonites. Inside this block the ore bodies are confined to systems of synthetic cracks of the cleavage of the northeastern orientation, made with quartz with pyrite impregnation.The Talayz deposit is a gently sloping mineralized zone (on average 30 m thick) in the horizon of melanocratic schists, beneath a screen of metavolcanics of acidic composition. Gold-bearing ones are: quartz-carbonate veins, lenses, veins, with extremely uneven distribution of sulphides and attached to zalband parts of quartz veins with the development of vein-disseminated sulfide mineralization. The position of the ore-bearing zones of the Vorga­vozh deposit is determined by the confinement to blastomylonites along the contact with the overlapping horizon of metavolcanics of acidic composition complicated by a series of northeastern tectonic disturbances. Ore-bearing zones (thickness 2-18 m) are represented by chlorite-muscovite-albite schists containing quartz, quartz-carbonate veins and veins, with vari­ous aggregates of pyrite and dissemination of chalcopyrite, and rarely, galena. From the given data the conclusion about high prospects of Precambrian structures of the Subpolar Urals on opening of new deposits of gold is made.

Alteration of water-resistance properties of overburden under influence of sulfuric acid

Integrated development of Volkov copper–iron–vanadium deposit is impossible without heap leaching of copper from old oxidized and complex ore stock pile. The current condition of the stock pile imposes risks of pollution on the Laya River water and on the topmost aquifer groundwater. The natural protection barrier between the groundwater and the old oxidized and mixed ore stock pile is rather good. Permeability of the upper layer of the stock pile, determined by the standard procedure in accordance with the construction norms and regulations, is classified with ambiguousness. For final decision-making after geological engineering survey, permeability characteristics of the upper layer were analyzed using different−concentration sulfuric acid solutions to simulate heap leaching conditions.

Wastelanding: Legacies of Uranium Mining in Navajo Country. By Traci Brynne Voyles

Wastelanding: Legacies of Uranium Mining in Navajo Country . By Traci Brynne Voyles. (Minneapolis: University of Minnesota Press, 2015. xv + 292 pp. Illustrations, maps, notes, bibliography, index. $87.50, cloth; $25.00, paper.) The history of Southwest uranium mining, and on the Navajo Reservation specifically, has been told several times over the last few decades. Beginning with radium mines on the Colorado Plateau at the end of the nineteenth century, private mining ventures expanded to uranium and vanadium deposits in the early twentieth century before the top-secret Manhattan Project reorganized the industry for national security during World War II. In the years of the Cold War, government incentives led to new discoveries, and mines developed across Dinetah to feed the growing nuclear power industry. But …