The grain size of columbite-tantalite in the concentrate is the coarsest, followed by that in the middlings, and the finest in the tailings, which are mainly distributed in the range of -150+38 ...Web
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Australia was initially the largest producer of columbite-tantalite in the world, closely followed by Canada and Brazil. In 2006 alone, the three countries had an 80% share of total columbite-tantalite produce. However, their production of coltan went downhill following environmental regulations and unsuccessful mining company buyouts.Web
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1 Geology. The primary ore of tantalum is the columbite-tantalite group. The columbite group is a solid solution with varying proportions of Nb or Ta in its …Web
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The age of apatite, cassiterite, columbite-tantalite (coltan) from five zones in Nanping No.31Li–Cs–Ta-rich type pegmatite deposit show remarkable two group ages (370–390 Ma and 145–160 Ma). ... and it is necessary to consider the applicability and limitations of various methods comprehensively. In addition to zircon, the CGMs ...Web
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Abstract. The increased demand of metals such as tantalum (Ta) and niobium (Nb) reflect the on-going development in modern science, engineering and technology. …Web
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The extraction and separation of pure Ta and Nb from each other and from the coexisting elements needs efficient beneficiation of columbite-tantalite.Web
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Coltan 139 and these three columbite-tantalite samples with variable compositions yielded internally consistent LA-ICP-MS U-Pb ages when using each other for calibration and the weighted mean 206 Pb/ 238 U ages are comparable to respective ID-TIMS ages. Composition-dependent U-Pb fractionation seems to be insignificant under …Web
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Of the 73 points analysed across 32 columbite-tantalite grains, 25 fell within ±2% of range. Of these, 24 points were identified as mangano-columbite and 1 as mangano-tantalite. ... The mineralogical characterization of tantalum ore is necessary to determine the grade that could be obtained during the ore processing. Nb and Ta occur …Web
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Nb and Ta-ore minerals are exclusively oxide minerals, such as columbite-tantalite. ... it is also necessary to have accurate knowledge of concentrations of Nb and Ta in the ore and products (May et al., 1961, Ruiz et al., 1993, Shikika et al., 2021). Thus, the choice and design of separation process technology for Ta and Nb is governed by ...Web
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Rare Tantalite Columbite crystal 1.31 oz specimen #4804T - DR Congo Rare Tantalite Columbite crystal 1.31 oz specimen #4804T - DR Congo 4.9 (3.3k) · a d ...Web
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Columbite-tantalite with high tenor of tantalum is mainly derived from pegmatit ic source. Large, low- grade deposits of pyrochlore, probably t he chief source of niobium, occur in.Web
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The generic term columbotantalite, cbt, comprises the different compositional varieties of columbite and tantalite, classically treated (e.g. Ramdohr 1980) as an isomorphic, continuous solid solution series between the members (Fe, Mn)Nb 2 O 6 (niobite, now columbite, cb) and (Fe, Mn)Ta 2 O 6 (tantalite, tan), a series also known …Web
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Columbite-tantalite LA-ICP-MS U-Pb dating is a fast and useful method to determine the age of rare-metal deposits and fingerprint the provenance of columbite …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, and optical property analyses of these minerals were performed. As a result of the structural studies and micro-area analyses, it was …Web
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Here, a nanoscale study of the columbite-tantalite mineral in the Zhaojinggou Nb-Ta deposit in North China Craton elucidated its formation mechanism and the role of fluids in Nb-Ta mineralization.Web
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In columbite-tantalite ores, Nb & Ta often occur in association with iron, manganese, titanium, rare-earths and trace level of uranium. Separation of radioactive element is necessary in the ...Web
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Compositionally, columbite-tantalite of the Li-albite granites is constrained between MnNb 2 O 6 and MnTa 2 O 6 (the Ta/(Nb+Ta) atom. ratio ranges between 0.10 and 0.80). This low to high ratio and the association of columbite-tantalite with topaz, fluorite and lithian micas (in the series zinnwaldite-white mica) indicate a higher solubility ...Web
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When exploring and exploiting minerals, it is necessary to critically consider the inherent mineral properties and the major compositions; as well as the behaviour or response during processing, ... Columbite usually occur together with the mineral tantalite as columbite-tantalite (coltan) in semi-singular mineral series and a combined form of ...Web
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Literature from previous studies indicates that Tantalite, Wolframite, Niobium, and Columbite possess the necessary potential to be developed as alternative sources of cobalt for lithium battery ...Web
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Tantalite is named after its tantalum content, and, together with Columbite, are the most important minerals containing the rare element tantalum. The name Tantalite has been …Web
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In this study, we examine the Ta-Nb oxide minerals from the granites, greisens and especially from related granitic pegmatites of the Bugarura–Kuluti …Web
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Columbite is generally described as a low-grade complex oxide ore of majorly metal oxide compounds like niobium penta-oxide (Nb 2 O 5) of ~ 55–78% content and ~ 5–30% tantalum penta-oxide (Ta 2 O 5) as its main constituents in the ore composition with significantly associated oxide gangue minerals/elemental impurities …Web
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It should be emphasized that, for a more precise attribution of the TMG as parental rocks for the spodumene pegmatites, it is necessary to undertake additional isotope-geochronological studies of mineral geochronometers (tantalite-columbite, apatite, cassiterite, etc.) extracted directly from the spodumene pegmatites.Web
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Note: tantalite and columbite are actually the name of mineral groups that are considered obsolete, and they are often combined under the larger group name "coltan"; it may be necessary to investigate these individually or together. For each of the minerals, list their chemical formula, Dana group, and crystal system.Web
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Columbite and tantalite solubilities in the granitic liquids increase by a factor of approximately 2 to 3 with the addition of 2 wt percent Li 2 O to haplogranite at 750 degrees to 1,035 degrees C, 2 kbars, and water-saturated conditions. The solubility data were extrapolated to a lower temperature, more reasonable for columbite-tantalite ...Web
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Introduction. Niobium and tantalum are critical metals that have been used increasingly in advanced technologies (e.g. information technology, energy, aerospace, national defence and military, Linnen et al., Reference Linnen, Van Lichtervelde and Černý 2012).Members of the columbite–tantalite solid-solution series are a major mineral …Web
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Therefore, a systematic study of texture, major-element composition, and U-Pb dating of columbite-tantalite group minerals (CGMs) in the spodumene pegmatite dyke from the CKBS deposit was undertaken. Three types of CGMs were identified, including concentric oscillatory ferrocolumbite (CGMs-1), homogeneous ferrocolumbite (CGMs-2), …Web
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The principal lithium ore minerals are spodumene, petalite, and lepidolite; cesium mostly comes from pollucite; and tantalum mostly comes from columbite-tantalite. Tin ore as cassiterite and beryllium ore as beryl also occur in LCT pegmatites, as do a number of gemstones and high-value museum specimens of rare minerals.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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In short, columbite-Fe is more common than columbite-Mn and in turn are both much more common than tantalite-Mn and the fourth example, tantalite-Fe, is actually very scarce. There are paragenetic guidelines. Associated iron and manganese bearing minerals tend to have a similar ratio of elements, but they need to be coeval.Web
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Columbite has the same composition and crystal symmetry (orthorhombic) as tantalite. In fact, the two are often grouped together as a semi-singular mineral series called columbite-tantalite or coltan in many mineral guides. However, tantalite has a much greater specific gravity than columbite, more than 8.0 compared to columbite's 5.2.Web
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1. Introduction. Columbite-tantalite (coltan) refers to a solid solution series, which is formed between two different minerals, namely columbite and tantalite with …Web
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Note: tantalite and columbite are actually the name of mineral groups that are considered obsolete, and they are often combined under the larger group name "coltan"; it may be necessary to investigate these individually or together. For each of the minerals, list their chemical formula, Dana group, and Crystal System in the table below.Web
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This zoning model, however, is not consistent because: (1) in the so-called (Li–)Sn zone, there is a considerable number of pegmatites that are devoid of cassiterite and only mined for tantalite/tapiolite, (2) cassiterite is a common accessory mineral, associated with columbite group minerals in the inner, so called Ta–Be zone (Da Silva et ...Web
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preparation of pure oxides of niobium and tantalum from indian columbite and tantalite Journal Article Sarma, B ; Gupta, J - Indian J. Tech. A promising solvent extraction procedure, employing cyclohexanone or methyl n-propyl ketone, was developed for the preparation of niobium and tantalum oxides of more than 99.9% purity from Indian …Web
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The dissolution of columbite-tantalite in HF can be represented by the following reactions (Gupta and Suri, 1993 However, these decomposition processes are associated with the loss of HF due to ...Web
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The trace phases include tantalite, columbite, cerianite-(Ce), thorite, changbaiite, cryolite, cassiterite, yttrocerite, yttrofluorite, Ca-Th-Pb fluorides, and Nb-rich oxides. Magma evolution and emplacement. The specific conditions necessary to form a REE-enriched deposit in highly evolved subalkaline rhyolites have not been well …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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Therefore, ore minerals of Nb and Ta are exclusively oxide minerals. Among them, minerals of wodginite and pyrochlore groups are important sources of Ta and Nb, respectively, although colombo-tantalite (Coltan) mineral group is the main source of both Ta and Nb (Table 1). The general formula of columbite-tantalite is AB 2 O 6. Where, "A ...Web
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