Effects of columbite/tantalite (COLTAN) mining
RESEARCH Open Access. Effects of columbite/tantalite (COLTAN) mining activities on water quality in Edege- Mbeki mining district of Nasarawa state, North Central Nigeria. …
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Extractive metallurgy of columbite-tantalite ore: A detailed …
The increased demand of metals such as tantalum (Ta) and niobium (Nb) reflect the on-going development in modern science, engineering and technology. The extraction of these two metals from columbite-tantalite ore is based on generic extractive metallurgy. However, the upstream purification of ore and downstream extraction of Ta …
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Columbite SN3: A New Potential Reference
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 …
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Late Neoproterozoic over of the cassiterite and columbite …
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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Mineral chemistry of columbite–tantalite from
In addition, the solubilities of columbite and tantalite increase with increasing temperature and Li content of the melt (Fiege et al., 2011). This trend culminates with late crystallization of tantalite and usually involves decreasing temperature, Li and F contents, leading to the deposition of Li- and F-bearing minerals (spodumene and ...
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ICP-OES determination of Nb, Ta, Ti, W, Sn, Zr, and Hf in columbite …
[Show full abstract] of columbite-tantalite [(Fe0.8Mn0.2) (Nb, Ta)2O6]. The analytical data obtained by application of this method to tin concentrate samples were compared with those obtained by ...
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Chemistry of columbite-tantalite minerals in rare metal …
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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Chemistry of columbite-tantalite minerals in rare …
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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Coltan | Earth Sciences Museum
Kathy Feick. Coltan is short for columbite-tantalite, a dull metallic ore. When refined, coltan becomes a heat resistant powder, metallic tantalum, which has unique properties for storing electrical charge. Coltan occurs in granitic pegmatites, pockets where the deep seated molten rock crystallized last. Pegmatites contain many rare metals, as ...
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Effects of columbite/tantalite (COLTAN) mining
Effects of columbite/tantalite (COLTAN) mining activities on water quality in Edege-Mbeki mining district of Nasarawa state, North Central Nigeria Mohammed Engha Isah1*, Nuhu Abdulkadir Abdulmumin2, Paul D. Elaoyi2 and Ephraim Audu3 Abstract Background: The release of environmental pollutants such as heavy metals due to mining activities has ...
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Chemistry of columbite-tantalite minerals in rare metal …
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 corrosive supercritical vapour phase. ... Reservoir Quality of Clastic and Carbonate Rocks: Analysis, Modelling and Prediction. The Black Pearl mine, Arizona; Wolframite veins and ...
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Tantalite-(Fe) Mineral Data
General Tantalite-(Fe) Information : Chemical Formula: Fe++Ta2O6 : Composition: Molecular Weight = 513.74 gm Tantalum 70.44 % Ta 86.02 % Ta 2 O 5 ... Tantalite - Columbite Series : 08.03.02.01 Tantalite-(Fe) FeTa2O6 Pcan 2/m 2/m 2/m : 08.03.02.02 Columbite-(Fe) ...
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Effects of columbite/tantalite (COLTAN) mining …
The range of pH was found to be from 5.6 ± 0.02 to 6.5 ± 0.12, turbidity was between 39.27 ± 0.29 and 2271 ± 0.00 NTU, and conductivity ranged from 39.27 ± 0.29 …
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A mixed collector system for columbite-tantalite flotation
Columbite-tantalite recovery was the highest at 3:1 BHA–SIBX among the tested collector suites. Using the 3:1 mixed BHA–SIBX collector yielded a more negative columbite-tantalite in comparison to that measured with BHA alone. This indicated the improved adsorption of the BHA–SIBX mixture on the columbite-tantalite surface and …
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What are conflict minerals?
What are conflict minerals? "Conflict minerals," as defined by the US legislation, currently include the metals tantalum, tin, tungsten and gold, which are the extracts of the minerals cassiterite, columbite-tantalite and wolframite, respectively. Downstream companies often refer to the extracts of these minerals as 3TG.
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Tantalite Value, Price, and Jewelry Information
These could be of any desired size. Tantalite is too dark to be of use as a faceted gem but is sometimes cut as a collector curiosity, either faceted or in cabochons. These could be of any desired size. TANTALITE Series to …
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What coltan mining in the DRC costs people and the …
The Democratic Republic of Congo (DRC) is rich in natural resources – its untapped deposits of minerals are estimated to be worth US$24 trillion.Gold, diamonds, cobalt and zinc are among them.
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Columbite SN3: A New Potential Reference Material for …
Geostandards and Geoanalytical Research is an international geoanalytics journal dedicated to geological reference materials, analytical techniques, and data quality. 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 ...
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Tantalite | mineral | Britannica
tantalite, tantalum-rich variety of the mineral columbite ( q.v.) with the chemical formula (Fe,Mn) (Ta,Nb) 2 O 6. Tantalite is the principal ore of the metal tantalum. This article was most recently revised and updated by …
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Mineralogy and chemistry of columbite-tantalite from …
The internal texture of columbite-tantalite exhibits a multiple zoning pattern indicating primary composition modified by the extreme fractionated, volatile and water saturated residual melt. Hydrothermal origin of columbite-tantalite is observed in greisens, expressed by a higher W concentration and coeval or even younger crystallization ...
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Columbite–Tantalite of the Kester Deposit (Eastern Yakutia)
Wolfram is a typomorfic impurity in columbite–tantalite of the Kester Deposit, WO 3 is 1.77%, on average (apfu is 0.03). In tantalite- (Mn), WO 3 is 0.70%, while in columbite- (Fe), WO 3 is 2.67%, reaching 7.12%. The wolfram impurity is more typical for columbite, whereas the tin impurity is typomorphic for tantalite: the average content of ...
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Columbite-Tantalite – WGNHS – UW–Madison
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 …
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Columbite-tantalite mineral chemistry from rare-element …
This study reveals that columbite-tantalite in the pegmatites has an extremely wide range of composition from primitive ferrocolumbite to evolved, almost end-member manganotantalite. Evidence is provided that melt evolution resulted in increased fluorine activity (as seen in microlite compositions) and that in situ fractionation of magma within ...
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Quantitative evaluation of metamictisation of columbite …
Members of the columbite–tantalite solid-solution series are a major mineral resource of Nb and Ta, and have the formula, AB 2 O 6, ... The accelerating voltage was adjusted between 15–20 kV to optimise image quality. The spot size of the electron beam was 3.9 μm. Electron back-scatter diffraction (EBSD) analysis of single-crystal …
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Columbite-tantalite (COLTAN) > ENGINEERING
COLTAN (Columbite-Tantalite) is a dull metallic ore found in major quantities in the eastern areas of Congo. When refined, COLTAN becomes metallic Tantalum, a heat-resistant powder that can hold a high electrical charge. Columbite ((Fe, Mn, Mg)(Nb, Ta) 2 O 6: Iron Manganese Magnesium Niobium Tantalum Oxide) is the …
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U-Pb isotopic dating of columbite-tantalite minerals: Development of
Columbite-tantalite U-Pb dating by isotope dilution thermal ionization mass-spectrometry has been reported for several geological contexts (ID-TIMS; ... Thus, the wide range of chemical compositions of columbite-tantalite minerals may strongly affect the accuracy and quality of in situ U-Pb dating if no adequate chemical standards are …
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Crystals | Free Full-Text | Columbite–Tantalite from Northern
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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Columbite: The mineral columbite-tantalite information …
Columbite is the niobium-rich member, and Tantalite is the tantalum-rich member. Columbite is named after its niobium content, which was previous known as columbium prior to its renaming. Columbite is the most important mineral containing the rare element niobium and is its main ore. The name Columbite has been discredited by the IMA, with …
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Mineral chemistry of columbite–tantalite from
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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Mineralogy and chemistry of columbite-tantalite …
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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