Columbite-tantalite minerals are potentially useful for dating the emplacement age of economically important rare-element pegmatites. Romer and Wright have shown that columbite-tantalite may accommodate considerable amounts of uranium (circa 500–1000 ppm) and exclude lead almost completely.The U-Pb systematics, …
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Columbite-tantalite group minerals (CGMs) are important sources of critical elements, i.e., ... The offline data processing was performed using the ICPMSDataCal program (Liu et al., 2008). The concordia U-Pb ages were calculated using the Isoplot 3.0 software (Ludwig, 2003).
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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-tantalite ore concentrates.
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After columbite-tantalite is activated with 60 mg/L Pb(NO 3) 2, the zeta potential of columbite-tantalite for the entire pH range is positively shifted, and the IEP increases from 3.7 to 5.8. The significant positive shift of zeta potential is attributed to the specific adsorption of positively charged Pb species onto the columbite-tantalite ...
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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.
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The columbite-tantalite commonly exhibits a mottled or patchy zoned texture with the rims consistently higher in Ta than the cores, reflecting the later effect of a …
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From core to rim, CGM crystals vary from columbite-(Mn) to tantalite-(Fe), recording magmatic fractionation. The Gaoling quartz vein contains homogenous CGM crystals that yield low Ta concentrations ( Figs. 2 and 3 c), likely reflecting the action of a hydrothermal fluid, as Nb has a low solubility and is fluid-mobile ( Linnen et al., 2014 ).
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Abstract. Columbite–tantalite (Coltan) is the most important niobium (Nb)- and tantalum (Ta)-bearing economic mineral, commonly occurring in rare metal granite and pegmatite, alkaline granite, syenite and carbonatite. Its high U but low common Pb contents make it an ideal mineral for U–Pb isotopic dating of Nb–Ta mineralization.
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Fluoride-Free Processing of Columbite Concentrate for Selective Recovery of Niobium and Tantalum Oxides. Published: 23 March 2024. ( 2024 ) Cite …
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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-tantalite ore concentrates. Accurate ...
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The conditions of tantalite (Congo deposit) and the decomposition of columbite (Zashikhinsk deposit) using an HF and H2SO4 mixture when heated to 80°C have been found. The extraction of Ta and Nb into solutions achieved levels of more than 99% and ∼94% for tantalite and columbite, accordingly. It has been found that …
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Since 2006, our working group has been investigating columbite-tantalite (coltan) mineralisation, especially in Africa, also within the wider framework of establishing certified trade chains.
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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 …
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This study presents a fluoride-free, rapid, and energy-efficient process for niobium and tantalum extraction from columbite using microwave-assisted alkali …
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Columbite–tantalite is common as elongate-prismatic subhedral crystals associated with muscovite and microcline as well as within albitite. Grains associated with albitite appear finer grained (50–150 µm, Fig. 4 a) and show oscillatory zoning more distinctly than CGM associated with pegmatitic muscovite and microcline (300–500 µm).
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Columbite has the same composition and crystal symmetry (orthorombic) 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.
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Combined mineralogical-geochemical-geochronological signatures of columbite-tantalite ores are used to trace the origin of ore concentrates. Location of important ore provinces with Nb-Ta mining ...
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The formation of columbite-group mineral phases in peraluminous granite has not been demonstrated to date. 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. Transmission electron …
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Columbite-tantalite series minerals from Li-Cs-Ta (LCT) pegmatites and peraluminous granites are not well constrained but do slightly overlap with columbite-(Fe) from carbonatites. A minor overlap exists between the fields from carbonatites, peralkaline complexes, LCT pegmatites, and peraluminous granites near the columbite-(Fe) corner …
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Methyltrioctylammonium chloride has been recently studied in the extraction of Nb and Ta from a HF-free leachate of columbite processing, ... Mn-rich columbite–tantalite is typical of the Alto ...
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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 ...
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We successfully report a liquid–liquid chemical reduction and hydrothermal synthesis of a highly stable columbite-tantalite electrocatalyst with remarkable hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performance in acidic media. The reduced Fe0.79Mn0.21Nb0.16Ta0.84O6 (CTr) electrocatalyst shows a low overpotential …
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The dependence of columbite–tantalite (Nb2O5-59 wt. %, Ta2O5-18 wt. %) solubility as a function of solution composition, T, and P has also been investigated. Tantalum and Nb concentrations have the highest values in HF solutions at reduced conditions (up to 10−3 to 10−2 m Ta in 1 m HF). In 1 m NaF solutions, the …
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Columbite-group minerals occur in all main parageneses of the pegmatites and form four generations, reflecting the sequence of pegmatite formation. These minerals demonstrate wide variations in the content of major and trace elements. The composition of CGM ranges from columbite-(Fe) to tantalite-(Mn).
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They display a wide range of composition including all types of columbite group minerals, wodginite, tapiolite and microlite. The internal texture of columbite …
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Skype of kangforui and mobile phone of +86- can be available every 24 hours. Skype: ForuiMining Mob: +86 Email: sales1@frjig. Your Contact Details To Us (*)Required information. The processing of tantalite-columbite ore is complex due to its low content and sophisticated composition. Usually, the enrichment flow sheet ...
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Columbite and tantalite are collectively known as coltan in Africa. Tantalum is a valuable rare element used in electronics manufacturing while columbite is used in forming alloys that are useful in nuclear, aerospace and gas turbine engineering. ... Report Title: COLUMBITE ORE MINING AND PROCESSING IN NIGERIA, THE PRE …
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Abstract. The Zashikhinsky massif is unique tantalum-niobium deposit of alkaline-granite type hosted by the Late Paleozoic rare-metal zone of magmatism in the East Sayan Mountains. Columbite is the mineral concentrating Nb, Ta and Y-group elements. It forms both large (2–5 mm) and small (smaller 0.5 mm) black grains, in …
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A primary processor is generally also able to process secondary concentrates (columbite or struverite), synthetic concentrates and/or scrap. The products of a primary processor may be anything from the most …
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Columbite-(Fe) in tabular crystal from the Nine Mile pluton near Wausau in Marathon County, Wisconsin. Scanning electron microscope image. (Photo by Al Falster.) Columbite-tantalite refers to a group of minerals having varying amounts of iron, manganese, niobium, and tantalum. They are found as platey black grains in complex granitic pegmatites. …
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Here, we report on new U–Pb age data from columbite-tantalite minerals and 40 Ar– 39 Ar age data on muscovite from the Gatumba area in Rwanda, forming part of the KAB (Fig. 2).The study area is situated in the western part of Rwanda, about 50 km west of Kigali and can be considered as representative of pegmatite mineralisation in the …
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1 Citation. Explore all metrics. Abstract. Three mineral types of the columbite group have been revealed at the Kester Deposit (Eastern Yakutia), that is, columbite- …
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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 …
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Open access. Published: 21 December 2017. Towards sustainable processing of columbite group minerals: elucidating the relation between dielectric properties and …
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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 ...
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