Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing pegmatites of the Gatumba area, Rwanda (Central Africa ravi chandra The Mesoproterozoic Kibara belt in Central Africa has recently been redefined and subdivided into the Karagwe–Ankole belt (KAB) and the Kibara belt (KIB), separated by Palaeoproterozoic ...

The Mesoproterozoic Kibara belt in Central Africa has recently been redefined and subdivided into the Karagwe–Ankole belt (KAB) and the Kibara belt (KIB), separated by Palaeoproterozoic (Rusizian) terranes. The KIB and KAB are characterised by the presence of numerous rare metal mineralised (Nb–Ta–Sn) pegmatites and Sn–W mineralised …

Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing pegmatites of the Gatumba area, Rwanda (Central Africa) ... The Mesoproterozoic Kibara orogen in Central Africa hosts different granite-related rare element deposits that contain cassiterite, columbite-tantalite ( coltan ), wolframite, beryl, spodumene, etc. …

Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing pegmatites of the Gatumba area, Rwanda (Central Africa) J. African Earth Sci. ... These metasedimentary rocks have been overprinted by Pan-African deformation and greenschist facies metamorphism in the late Neoproterozoic (e.g., Van Daele et al., …

Few investigations have focused on the potential uses of artisanal gold (Au) mine tailings, despite the fact that artisanal gold mining activity contributes to environmental issues such as greenhouse gas. …

The mesoproterozoic Kibara belt in central Africa has the subdivision of the two mobile belts which are the Karagwe -Ankole belt (KAB) and the Kibara belt (KIB), separated by Rusizian terrane. The KAB, which spans Rwanda, Burundi, Southwestern Uganda and Northwestern Tanzania, and the KIB together host a large metallogenic province that is composed of …

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 …

The pegmatites are mineralised with columbite-tantalite and cassiterite. Recent investigation by Dewaele et al. (2007a Dewaele et al. (, 2008 indicates that the columbite-tantalite mineralisation ...

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 …

Dewaele S, Henjes-Kunst F, Melcher F, Sitnikova M, Burgess R, Gerdes A et al. Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing …

The 40 Ar- 39 Ar spectra of muscovite samples associated with different steps in the paragenesis of the pegmatites show a spread of apparent ages between ∼940 Ma …

Here, we provide cassiterite and columbite-group mineral (CGM) U-Pb ages along with oxide, mica and phosphate mineral compositions for Li-pegmatites from the Fregeneda-Almendra field in order to ...

Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing pegmatites of the Gatumba area, Rwanda (Central Africa ravi chandra The Mesoproterozoic Kibara belt in Central Africa has recently been redefined and subdivided into the Karagwe–Ankole belt (KAB) and the Kibara belt (KIB), separated by Palaeoproterozoic ...

A swarm of pegmatite dykes generally strike NW, NE, and nearly N–S (Fig. 2), with a dipping angle of 10°–85°, which formed sharp contacts with the surrounding wall-rocks.The rare-metal pegmatites belong to the beryl-type (e.g., beryl–columbite subtype) and complex-type (e.g., spodumene subtype and lepidolite subtype; Zhou et al., 2019) …

Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing pegmatites of the Gatumba area, Rwanda (Central Africa) J. Afr. Earth …

Semantic Scholar extracted view of "Geological setting and timing of the cassiterite vein type mineralization of the Kalima area (Maniema, Democratic Republic of Congo)" by S. Dewaele et al. ... which are associated with equigranular to pegmatitic late Mesoproterozoic (1094–755 Ma) granites ... Late Neoproterozoic over of the ...

Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing pegmatites of the Gatumba area, Rwanda (Central Africa) S. Dewaele F. Henjes‐Kunst +7 authors B. Lehmann Geology

The Nuweibi rare-metal granite in the Central Eastern Desert of Egypt is highly evolved fine- to medium-grained leucogranite affected by pervasive albitization and greisenization. The intrusion holds an important tin–tantalum resource in the Egyptian Eastern Desert. Columbite–tantalite and cassiterite disseminations occur within the …

Cassiterite and columbite-tantalite mineralization can be found in the more evolved pegmatites, pegmatites of the LCT-type (Lithium Caesium Tantalum)-type according the paragenetic-geochemical classification scheme of Cerny (1991). ... & Lehmann, B., 2011. Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing ...

It provides economic minerals of cassiterite, columbite-tantalite, spodumene, wolframite, monazite as well as some rare earth minerals [4-6]. ... Dewaele, S., Henjes-Kunst, F., Melcher, F., et al. (2011). Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing pegmatites of the Gatumba area, Rwanda …

Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing pegmatites of the Gatumba area, Rwanda (Central Africa) ... of apparent ages between ∼940Ma and ∼560Ma that ...

Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing pegmatites of the Gatumba area, Rwanda (Central Africa) | Semantic …

Tantalum, niobium, tin, and tungsten mineralization typically occurs worldwide in close proximity to fractionated peraluminous leucogranites. These granite-related ore deposits show a diversity of mineralization modes, ranging from plutonic-hosted breccia and hydrothermal vein-stockwork systems to (peri)batholitic greisens, skarns, …

Previous works on pegmatites were geochemistry and geological maps which are not enough for focused exploration and mine planning. Therefore, geological, petrographic, geochemical studies of neoproterozoic rare element pegmatites of Gatumba and Gitarama areas in relation to their mineralisation were carried out.

Secondary Ionisation Mass Spectrometry (SIMS) U-Th-Pb dating of cassiterite with very low to sub-ppm U contents, zircon and monazite has provided direct measurements of the ages of Mesoproterozoic–Neoproterozoic pegmatite and quartz vein Sn mineralisation in the Karagwe–Ankole Belt (KAB), Rwanda, and through dates on …

Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing pegmatites of the Gatumba area, Rwanda (Central Africa) August …

Late Neoproterozoic over of the cassiterite and columbite-tantalite bearing pegmatites of the Gatumba area, Rwanda (Central Africa) Journal Contribution - Journal Article ...

In April 2016 Manchester eScholar was replaced by the University of Manchester's new Research Information Management System, Pure. In the autumn the University's …

The Mesoproterozoic Kibara orogen in Central Africa hosts different granite-related rare element deposits that contain cassiterite, columbite-tantalite ( coltan ), wolframite, beryl, spodumene, etc. as typical minerals. The primary deposits of these minerals are formed by pegmatites and quartz veins that have historically been related to the youngest, most …

The No. 31 vein is identified as pegmatite by CMS features. New U–Pb dating CGMs (columbite-tantalite group minerals) in five zones have a consistent age (380 ± 10 Ma). Whilst U–Pb dating of apatite and cassiterite from different structural zones show remarkable two group isotopic ages (370–390 Ma and 145–160 Ma).