Metallographic and in situ compositional study on …
The main compositions identified are columbite-(Mn) and columbite-(Fe), but Fe- and Mn-tantalites are also important minerals as well as ixiolite–wodginite. Most …Web
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The main compositions identified are columbite-(Mn) and columbite-(Fe), but Fe- and Mn-tantalites are also important minerals as well as ixiolite–wodginite. Most …Web
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For the niobium minerals pyrochlore and columbite-(Mn) in ASI 1.0 (ASI Li 0.83) melts, the solubility product of pyrochlore is almost identical to that of microlite (−3.71 mol 3 /kg 3 and -3.78 mol 3 /kg 3 respectively at 750 °C) and columbite-(Mn) has a slightly lower solubility product from that of tantalite (−2.68 mol 2 /kg 2 and -2.32 ...Web
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columbite, hard, black (often iridescent), heavy oxide mineral of iron, manganese, and niobium, (Fe, Mn)Nb 2 O 6. Tantalum atoms replace niobium atoms in the crystal structure to form the mineral tantalite, which is similar but much more dense.These minerals are the most abundant and widespread of the naturally occurring niobates and tantalates and …Web
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The LFGs of the Abu Dabbab massif containing Ta-bearing cassiterite, tantalite-(Mn), columbite-(Mn), microlite, and wodginite are considered as ores [27,34] (Figure 1b). Based on our petrographic study, the LFGs of the main phase are medium-grained white/light-gray rocks with massive texture that become green-gray amazonite at …Web
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O) are also known, in association with columbite-tantalite and beryl, from the pegmatites in other parts of Odisha, e.g., Pandikimal and Bathlaira in the Jharsuguda district (northern Odisha), and Baghnadi in the Phulbani district (Ramesh Babu, 1999; Singh and Viswanathan, 2015). Minor amount of zinnwaldite occurs in theWeb
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Columbite-tantalite and cassiterite are the predominant oxide species. On the basis of columbite-tantalite compositions, the ... Minor microlite, antimonian microlite and stibiomicrolite are found ...Web
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The rare metal minerals, identified from six mineralized pegmatites at Govindpal, Mundaguda, Mundval, Dhuramagurah, Haladikunda and Bacheli, include cassiterite, columbite–tantalite, wodginite, microlite, fersmite and Hf–zircon. Ta–Nb-poor cassiterite is ubiquitous and the most abundant ore mineral in all the mineralized …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 patterns are …Web
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Li-F granites from the Kester deposit (Yana Plateau in Yakutia, Russia) are proved to be connected with a rare-metal complex of accessory minerals: montebrasite, columbite-(Mn), columbite-(Fe), tantalite-(Mn), Ta-bearing cassiterite, U-bearing microlite, W-bearing ixiolite, niobian ferberite, U–Hf-rich zircon, and Ta-bearing rutile. …Web
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The main compositions identified are columbite-(Mn) and columbite-(Fe), but Fe- and Mn-tantalites are also important minerals as well as ixiolite–wodginite. Most of the minor mineral phases occur as small inclusions in columbite–tantalite and consist of cassiterite, zircon, struverite and microlite group minerals.Web
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Pegmatite veins bear diverse Ta minerals (columbite, tantalite-columbite, manganotantalite, ixiolite, and microlite) that accumulated rare metals late during the evolution of the pegmatite magmatic system. The discovered mineralogical and geochemical criteria are useful for exploration purposes.Web
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Tantalite is the tantalum-rich member, and Columbite is the niobium-rich member. 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 discredited by the IMA, with the more specific designations of Tantalite- (Fe) (also known ...Web
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The late tantalite-(Mn) (Fig. 8) is depleted in LREE (total REE up to 0.58 ppm) probably due to its co-crystallization with microlite containing high levels of REE. …Web
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Basically, columbite and tantalite occurs naturally in solid HMs that appear generally in granite pegmatites, alkali-granitic rocks and placer deposits with microlite, cassiterite, wodginite ...Web
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Member of: Columbite Group > Columbite Supergroup. Name: From the manganese content and for the Greek mythical figure Tantalus - for its difficulty in dissolving. Type Locality: ⓘ Utö Mines, Utö, Haninge, Stockholm County, Sweden. Tantalite- (Fe)-Tantalite- (Mn) Series and Columbite- (Mn)-Tantalite- (Mn) Series. Formerly known as ...Web
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In the Yichun granite complex (SE China), columbite group minerals, microlite and cassiterite are the main Nb, Ta, Sn-bearing minerals. They are mainly concentrated in the uppermost albite-lepidolite granite. Rutile is the only Nb, Ta-bearing phase in the geochemically primitive muscovite-zinnwaldite granite.Web
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In columbite tantalite and microlite niobium and tantalum constitute a solid solution, with their relative ratios distributed in different ways, giving place to uniform or zoned minerals. The structural characterization of these minerals is very important to design the milling operations during the processing in order to obtain the desired ...Web
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Back scattered electron (BSE) images have indicated complex zoning patterns such as oscillatory, patchy and/or their combinations, associated with replacement of columbite-tantalite by microlite ...Web
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The first three analyses are for microlite-II after wodginite; 6 and 7 for microlite-II after columbite–tantalite; 3, 4 and 5 for microlite-II surrounding quartz vein (Fig. 4d) and 78 to 80 are for cassiterite-II in the close vicinity of such microlite. Data are from single point analysis. n.d. = not detected. daguda pegmatite are higher.Web
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Here, we document the Ta-rich oxide minerals, such as those of the columbite–tantalite group, tapiolite-(Fe) and microlite. It is possible to distinguish a …Web
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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 …Web
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Apart from minerals of columbite-tantalite series, there is a range of other important accessory minerals containing the Nb-Ta oxides such as pyrochlore, tapiolite, microlite, wodginite, and ...Web
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It occurs as fine-grained disseminated columbite-tantalite and microlite (Reyf et al. 2000; Webster et al. 2004; Dolgopolova et al. 2004). Intense albitization and greisenization was accompanied by formation of amazonite, lepidolite and zinnwaldite (Reyf et al. 2000). A lamprophyre dike cross cuts the mineralization (Fig. 12).Web
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Pegmatite veins bear diverse Ta minerals (columbite, tantalite-columbite, manganotantalite, ixiolite, and microlite) that accumulated rare metals late during the …Web
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This study describes the solubility of wodginite, titanowodginite, microlite, and pyrochlore in comparison to columbite-(Mn) and tantalite-(Mn) in a H 2 O saturated flux …Web
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Dissolution textures resulting from the corrosion of columbite and tantalite rims, in particular, are common. The Mn/(Mn + Fe) ratio varies between 0.33 and 0.97 and the …Web
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Especially the association of columbite–tantalite with microlite and wodginite has been described as primary magmatic (Van Lichtervelde et al. 2007). However, at Kenticha, microlite-group minerals are clearly secondary in origin, replacing Mn-bearing columbite/tantalite. Ta mineralization at Kenticha is not accompanied by cassiterite.Web
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The Tin Mountain mine, located 20 miles (13.5 km) west of Custer, produced very little tin (cassiterite) but mined spodumene, pollucite, with minor amounts of beryl, columbite-tantalite, microlite ...Web
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Columbite-(Mn), tantalite-(Mn), microlite, pyrochlore, wodginite and titanowodginite are important ore minerals of niobium and tantalum and comprise the main sources of these strategic metals worldwide. The solubility of columbite-(Mn) and tantalite-(Mn) in haplogranitic melts has been well studied (e.g. Aseri et al., 2015; Linnen and …Web
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Results demonstrate that the main tantalum-niobium minerals include tantalite, columbite, tantalum-niobite, and microlite; these minerals are finely disseminated and nearly below 0.040 mm in size. The occurrence of niobium minerals is more complex than that of tantalum minerals; thus, a lower recovery for niobium than …Web
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ABsrRAcr Compositions of 45 ferrotapiolite-tantalite pairs from 12 granitic pegmatites were analyzed by electnon microprobe to establish empirically the shape, extent and position of the two-phase field in the columbite quadrilateral. The field is perceptibly broader than that defined earlier on the basis of single-phase samples. The compositions …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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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 ...Web
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Solubility of wodginite, titanowodginite, microlite, pyrochlore, columbite-(Mn) and tantalite-(Mn) in flux-rich haplogranitic melts between 700° and 850 °C and 200 MPa Alysha G. McNeil, Robert L. Linnen, Roberta L. FlemmingWeb
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Tantalum mineralization is formed within massif as fine-grained Ta–Nb mineralization (columbite–tantalite, microlite). It is known that the Ta and Nb concentrations in melt do not reach saturation limits required to crystallize the columbite–tantalite at the magmatic stage (Chevychelov, 2013), which suggests their …Web
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The most common are columbite, tantalite and microlite. Columbite and tantalite are the end members of a solid-solution called the columbite-group minerals, (Fe,Mn)(Nb,Ta) 2 O 6. Microlite, (A) 2 (B) 2 6 (O,OH,F)), with A=REE,U,Y, Ca,Na nd B=Ta,Nb, Ti, is the Ta-rich member of the pyrochlore group minerals. Tantalum canWeb
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Microlite-group minerals occur as common replacement products after primary and secondary columbite-group minerals (CGM) in albitised blocky K-feldspar and in coarse-grained, muscovite-rich units of the Schinderhübel I, Scheibengraben and Bienergraben beryl–columbite pegmatites in the Maršíkov District (Silesian Unit, Bohemian Massif, …Web
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columbite, tantalite, microlite and spodumene (von Knorring. and Fadipe, 1981; Boelema and Hira, 1998). Some of the. pegmatites in the Kenhardt and Gordonia districts (South Africa)Web
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The most common are columbite, tantalite and microlite. Columbite and tantalite are the end members of a solid- solution called the columbite-group minerals, …Web
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