In general, from textural and compositional data, it could be interpreted that the columbite-tantalite mineral and other rare-elements were developed from magmatic source, however, later on, overprinted by hydrothermal replacements. ... The samples were analysed for major elements, and trace and rare earth elements by ICP-AES and ICP …Web
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New data on rare earth element (REE) concentrations and distribution patterns of columbite-tantalite minerals from Ta-ore provinces worldwide are presented. …Web
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The Cape Cross–Uis pegmatite belt, Damara Orogen, north-central Namibia hosts multiple Ta–Nb- and Sn-oxide-bearing pegmatites. Columbite-group minerals, tapiolite, cassiterite and minor ixiolite and wodginite occur in abundance within pegmatites and display various compositional and internal structural mineralogical variations.Web
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Columbite-(Fe) is a post-magmatic accessory mineral occurring within syenogranites and greisens from the Desemborque Pluton. The petrographic (SEM) and geochemical (EPMA and LA-ICPMS) …Web
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The rare-earth elements (REE) in the columbite of V ish-teritsa are in the range 356–733 ppm (sum of REE, T able 5). The mineral is enriched in heavy REE (HREE: 306–697 ppm)Web
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Mineralogy of columbite-group minerals from the rare-element pegmatite dykes in the East-Qinling orogen, central China: Implications for formation times and ore …Web
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Columbite from British Columbia (9-10% U/sub 3/O/sub 8/), although apparently homogeneous when examined by means of x-ray diffraction methods, is shown to be a mixture of non- radioactive columbite and radioactive, metamict pyrochlore by means of an electron microprobe analysis. ... NIOBIUM-ZIRCONIUM-THORIUM-URANIUM AND …Web
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Columbite-tantalite group is a mineral used widely in technology. Electronics, automotive systems and health products like the pacemaker need this mineral to. ... Rare earth metals are found in varying quantities in smartphones. Neodymium, dysprosium, praseodymium, terbium, gadolinium and lanthanum are found inside displays and other …Web
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In all of these deposits, Nb and Ta commonly occur as relatively rare oxides, notably pyrochlore–microlite and columbite–tantalite, rather than as pure metals (Mackay and Simandl, 2014). Rock-forming micas also have a preference for Nb and Ta, with mineral–melt partitioning coefficients of >1 (Nash and Crecraft 1985), and play a key role ...Web
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Rare earth elements have played a key role in technological advancement, attracting great visibility in the global commodity market. ... Mineralogy of columbite-group minerals from the rare-element pegmatite dykes in the East-Qinling orogen, central China: Implications for formation times and ore genesis. Journal of Asian Earth Sciences, …Web
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The group of the rare earth elements (REEs) serves as valuable indicator of numerous geological processes such as magma formation or fluid–rock interaction. The decay systems of the radioactive REE isotopes 138 La, 147 Sm and 176 Lu are used for geochronometric dating of a range of events, starting from first steps of planetary …Web
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New data on rare earth element (REE) concentrations and distribution patterns of columbite-tantalite minerals from Ta-ore provinces worldwide are presented. The …Web
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The possible role of rare-earth elements (REEs) as a factor contributing to the high levels of sample discrimination was explored. These results provide additional evidence that LIBS has the potential to be utilized in the field as a real-time screening tool to discriminate between columbite–tantalite ores of different provenance.Web
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Estimates of the pegmatite bulk compositions indicate that they are granitic, and that the abundances of the fluxing components (B, P, and F), rare alkalis (Li), alkaline earth metals (Be), and high field …Web
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The average composition of columbite-tantalite (n = 10) reveals appreciable rare-earth (1209 ppm TREE) content (Tikoo et al. 2008). Spodumene has widespread occurrences (Sadashivaiah et al. 1980 ; Devaraju et al. 1990 ; Krishna and Thirupathi 1999 ), and is the most preferred ore mineral for economic extraction of Li due to high Li content …Web
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New data on rare earth element (REE) concentrations and distribution patterns of columbite-tantalite minerals from Ta-ore provinces worldwide are presented. The REE …Web
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It is famous for its rare-element (REL) reserves, but its genesis is unraveled. We present in-situ major- and trace-element chemistry and U-Pb dating analysis of …Web
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Niobium and tantalum, rare metals and high field strength elements (HFSEs) that are essential to modern technologies, are concentrated among others in lithium-cesium-tantalum (LCT) pegmatites and rare metal granites. The most important hosts for Nb-Ta in these types of deposits are the columbite group minerals (columbite-tantalite), but at …Web
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Reported host minerals for the tantalum and niobium in these deposits include natroniobate at Toongi 4, columbite and yttrium-bearing rare-earth niobates at Brockman 5, and columbite, niobium-enriched titanium minerals (ilmenite, rutile) and pyrochlore at Mount Weld 6. Tantalum grades in these deposits are comparable to those in the …Web
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@article{Zhou2021MineralogyOC, title={Mineralogy of columbite-group minerals from the rare-element pegmatite dykes in the East-Qinling orogen, central China: Implications for formation times and ore genesis}, author={Qifeng Zhou and Kezhang Qin and Dongmei Tang}, journal={Journal of Asian Earth Sciences}, year={2021}, …Web
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New data on rare earth element (REE) concentrations and distribution patterns of columbite-tantalite minerals from Ta-ore provinces worldwide are presented.The REE geochemistry was studied by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Five major types of chondrite-normalized REE distribution …Web
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Columbite-(Fe) is a post-magmatic accessory mineral occurring within syenogranites and greisens from the Desemborque Pluton. The petrographic (SEM) and geochemical (EPMA and LA-ICPMS) examination of this mineral shows two distinct textural types within both the rocks, named columbite-1 and columbite-2. The columbite-1 type …Web
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There are a large number of rare-metal pegmatites that formed through crustal melting in the Chinese Altai, but what controls rare-metal enrichment remains enigmatic. Here, a new columbite U Pb age of pegmatite mineralisation (247 ± 1 Ma) that is distinct from the ages of surrounding biotite granites (290–270 Ma) in the Dakalasu Be–Nb–Ta ...Web
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Abstract. New data on rare earth element ( REE) concentrations and distribution patterns of columbite-tantalite minerals from Ta-ore provinces worldwide are …Web
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LCT (lithium–cesium–tantalum) pegmatites from the Kaustinen and Kolmozero regions contain columbite–tantalite mineralization, which has been presented in this study. Crystal structure, Raman microscopy, …Web
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The columbite minerals occur in magmatic deposits of W, Sn, and rare earth elements (REE), alkaline and carbonatitic intrusions, and pegmatites . Coltan, a dark ore of columbite-group minerals, is an important source for the strategic elements niobium and tantalum and, for this reason, ignited and funded armed conflicts in some African ...Web
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New data on rare earth element (REE) concentrations and distribution patterns of columbite-tantalite minerals from Ta-ore provinces worldwide are presented. The REE geochemistry was studied by laser ablation inductively coupled …Web
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Rare earth elements (REE) have critical importance in the manufacturing of many electronic products in the high-tech and green-tech industries. Currently, mining and processing of REE is strongly concentrated in China. ... Columbite (Fe,Mn) (Nb,Ta) 2 O 6 is the most common niobium-bearing mineral in many of the studied samples.Web
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The composition of the fluid phase is often a poorly constrained variable in many ore deposits. In this study, we used calcite-fluid partition coefficients extrapolated to the P-T conditions of mineralization using the lattice strain model to reconstruct the composition of the hydrothermal fluids associated with different stages of the …Web
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Rare earth elements (REEs): ... The WSGS estimates 325 pounds of columbite-tantalite were produced from tin-bearing pegmatites and beryl-rich pegmatites in Wyoming, although further details are lacking. In 1942, …Web
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Raman spectroscopic analysis was performed on columbite-(Mn) samples from a variety of previously studied rare-element pegmatites in Xinjiang, China, including the Jing'erquan No. 1 spodumene-subtype, Dakalasu No. 1 beryl–columbite-subtype and Kalu'an spodumene-subtype pegmatites, to quantify the relationship between the degree …Web
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1. Introduction. Although peralkaline granites are a relatively rare occurrence in the Earth's crust, a disproportionally large volume of petrological literature has been devoted to their study due to their unique geochemical characteristics and important economic significance (e.g., Martin and Bonin, 1976, Martin et al., 1994, Liverton and Botelho, …Web
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The Bayan Obo deposit is the largest rare-earth element (REE) resource, and the second largest niobium (Nb) resource, in the world. In this paper, chemical analysis, field-emission scanning electron microscopy (FESEM), energy dispersive spectrometry (EDS), and an advanced mineral identification and characterization system (AMICS) …Web
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The rocks contain the highest Ta contents in Russia (Mashkovtsev et al. 2011), and they are enriched in Y-group rare-earth elements. The agpaitic granites are unique in that columbite is the major mineral concentrating rare elements, similar to Li-F granites of Trans-Baikal area and Mongolia.Web
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Columbite-tantalite-bearing granitoids of the Eastern Desert province of Egypt can be categorized into: (i) metaluminous alkali granites; (ii) peraluminous Li-albite granites; and (iii) metasomatized biotite and/or muscovite granite (i.e. apogranites). Columbite of the alkali granite is of FeNb 2 O 6 composition and associated with annite. The ...Web
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Major and some minor elements were quantified by XRF, while trace elements and rare earth elements were measured by ICP-MS, following the analytical procedures developed by Refer ence [ 33Web
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Large deposits of 15 rare earth elements (REE) were recently found in Andhra Pradesh's Anantapur district, reported The Times of India. These elements were found by the Hyderabad-based National Geophysical Research Institute (NGRI). According to the report, these elements are crucial components, which are used in a variety of daily-use …Web
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