The corrosive and volatile nature of chlorinating agents used in the chlorination process of columbite-tantalite complicates the process (Ma, 2012, Poupard …

The recent work related to columbite-tantalite chemistry from the Kibara Belt was mainly focused on building an African-scale database to identify regional and local differences in Ta-Nb deposits (Melcher et al., 2015). In the research they correctly noticed a wide compositional range of Ta-Nb oxides with predominance of CGM, however no ...

Abstract. We successfully report a liquid–liquid chemical reduction and hydrothermal synthesis of a highly stable columbite-tantalite electrocatalyst with remarkable …

F. H. Mohamed. Article. Metrics. Get access. Cite. Rights & Permissions. Abstract. Paragenetic, textural, and chemical characteristics of columbite-tantalite …

The first applications of LA-ICP-MS for dating columbite-tantalite used non-matrix matched minerals like zircon or monazite (i.e., Smith et al., 2004; Melleton et al., 2012). During the last years ...

The Mineral tantalite. Tantalite forms a solid solution series with Columbite known as the Columbite-Tantalite series. Tantalite is the tantalum-rich member, and Columbite is …

tantalite ore prices had remained at $193 per kilogram of contained Ta 2 O 5 since november 2014. The increases in price in 2018 were thought to have resulted from a combination of increased demand from downstream consumers, increased royalties on exports of columbite-tantalite ore signed into law by the Government of Congo …

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 …

Request PDF | LA-ICP-MS U–Pb zircon, columbite-tantalite and 40Ar–39Ar muscovite age constraints for the rare-element pegmatite dykes in the Altai orogenic belt, NW China | The Chinese Altai ...

Columbite-tantalite (CGM) ore, which represents a major source of Nb and Ta, ... 2012, Yang et al., 2014, Zhang et al., 2017). The Gaoling W–Nb–Ta deposit is hosted in two-mica granite that yields a zircon LA–ICP–MS U–Pb age of 220 ± 2 Ma (Zhang et al., 2015). Sample GL was collected from a CGM- and scheelite-bearing quartz vein.

Columbite-tantalite, cassiterite and other Ta-Nb-Sn oxides in sediments from catchments that contain known LCT pegmatite occurrences show the same textural and chemical characteristics as these ...

* Correspondingauthor Accessory Fe-rich columbite-group minerals, tapiolite and Hf-rich zircon occur in Hercynian pegmatitic leucogranite near Duchonka, Považský Inovec Mts., western Slovakia. The host rock represents highly peraluminous and fraction- ated S-type pegmatitic leucogranite with ASI = 1.27, Eu N /Eu* N = 0.16, Rb/Sr = 7.2, …

Tantalite is the principal ore of the metal tantalum. This article was most recently revised and updated by Amy Tikkanen. Columbite, hard, black (often iridescent), heavy oxide mineral of iron, manganese, and niobium, (Fe, Mn)Nb2O6. Tantalum atoms replace niobium atoms in the crystal structure to form the mineral tantalite, which is similar but ...

The columbite group is a solid solution with varying proportions of Nb or Ta in its composition. According to the International Mineralogical Association (IMA), 'tantalite' or 'coltan' are not scientific names, yet they are widely used. Many specimens commonly named tantalite are actually minerals of the columbite or tapiolite group ...

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- …

Abstract. Columbite–tantalite (Coltan) is the most important niobium (Nb)- and tantalum (Ta)-bearing economic mineral, commonly occurring in rare metal granite …

Columbite forms a solid solution series with Tantalite known as the Columbite-Tantalite series. Columbite is the niobium-rich member, and Tantalite is the tantalum-rich …

The industrial processes for recovery of niobium and tantalum oxides depend on hydrofluoric acid, which is a highly toxic and corrosive reagent with significant environmental consequences. This study presents a fluoride-free, rapid, and energy-efficient process for niobium and tantalum extraction from columbite using microwave-assisted …

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 ...

The columbite-tantalite group minerals [(Fe,Mn)(Nb,Ta) 2 O 6 ] are critical ore minerals of niobium and tantalum in rare metal pegmatite deposit.

Both Kabangu and Crouse (2012) and Nete et al. (2014d) were able to recover more than 90 % of Nb and Ta from columbite-tantalite ore using NH 4 HF 2 …

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 ...

The columbite–tantalite samples selected for this pilot study come from three pegmatite locations in North America: (1) the Starrett pegmatite in southern Maine; (2) the BeeBee/PackRat pegmatite in San Diego County, California; and (3) the Moose pegmatite in the east-central Northwest Territories, Canada [6–12].The 14 samples …

These pegmatites are mostly hosted by gabbros (Lindroos et al., 1996) and their distribution is shown in Figure 5 of Eilu et al. (2012). Feldspar quarrying in Kimito followed previous quartz extraction for glass and iron works, presumably since about 1686. In 1737, the occurrence of tantalite was described from the Skogsböle pegmatite.

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 …

be exhausted tin–rare-metal ores. The Kester Deposit is an ore-bearing greisen. deposit that is located at a hanging endocontact of a. harpolith of rare-metal granites at its bend, and sub-. m e ...

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 ...