The columbite-tantalite group of minerals in different pegmatite groups show compositional variability and this is directly dependent on the crystallization condition of an individual granite ...
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 ...
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 ).
The accessory mineral assemblage separated from the waste is described. It is rich in columbite-tantalite, rutile and cassiterite with minor amounts of apatite, zircon and monazite. There is a wide range of chemical variation shown by the columbite-tantalite and rutile, and two types of monazite occur.
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 …
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).
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 …
Abstract. We successfully report a liquid–liquid chemical reduction and hydrothermal synthesis of a highly stable columbite-tantalite electrocatalyst with remarkable …
The present review focuses on the effective beneficiation of columbite-tantalite, extraction and purification of Ta and Nb using various technologies and the …
Htwe and Lwin (2008) studied on the extraction of niobium oxide from columbite-tantalite concentrate. With the original Columbitetantalite concentrate containing 19.29% Nb 2 O 5, 9.93% Ta 2 O 5 ...
They display a wide range of composition including all types of columbite group minerals, wodginite, tapiolite and microlite. The internal texture of columbite …
Also, the most commonly available ore of tantalum, coltan also called columbite-tantalite, is a mixture of two minerals, i.e., columbite (mineral of Niobium) and tantalite (mineral of tantalum ...
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 ...
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 ...
At room temperature no contact was observed on clean surfaces of columbite or tantalite specimens in solutions containing sodium oleate alone. Columbite was tested through the range pH 2.5 to …
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 …
LCT (lithium–cesium–tantalum) pegmatites from the Kaustinen and Kolmozero regions contain columbite–tantalite mineralization, which has been presented in this …
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 …
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.
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 ...
3.1 Feed Characterization. Table 1 shows the chemical analysis of the columbite concentrate used in this study. The feed sample comprises 21.9% niobium, 3.5% tantalum, 25.9% tin, 11.6% iron, 0.9% manganese, 0.8% silicon, and 0.4% aluminum. XRD analysis (Fig. 1) shows that ferro-columbite and tantalite are the primary niobium …
The patchy zoning is the most common texture of CGM in the Bugarura-Kuluti. It is often produced when columbite-tantalite is subjected to an alteration by later fluids (Tindle and Breaks, 2000). Usually, an early columbite generation is replaced (or partially replaced) by a later columbite-tantalite generation richer in Ta (Fig. 8 a–c).
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 …
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. …
This study presents a fluoride-free, rapid, and energy-efficient process for niobium and tantalum extraction from columbite using microwave-assisted alkali …
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.
The procedure can be applied for the determination of these elements in columbite/tantalite. The main advantage of the method is the ICP-OES determi- nation of Nb and Ta, and associ- ated elements ...