 | | Journal (article/letter/editorial) | | from rare-metal pegmatites in South Africa and Namibia JoY R. BALDWIN Department of Geology, University...from rare-metal pegmatites in South Africa and Namibia have been investigated with the electron microprobe...microprobe. A uranmicrolite from Karibib, Namibia contained 14.35% UO2, 1.03% PbO, 56.12% Ta205, 13.18% Nb205...traverses across a 1.3 mm uranoan microlite, Tantalite Valley, Namibia, revealed two essentially distinct compositions:...manganotantalite, ferrotantalite, South Africa, Namibia, replacement. Introduction MICROLITE minerals |  | | Report (issue) | | SURVEY NAMIBIA 1990 Open File Report MRS 12 2 Abstract Niobium-tantalum mineralisation in Namibia occurs...niobium-tantalum pentoxides of the columbite-tantalite series, or as niobium-tantalum minerals of the...pyrochlore group. Minerals of the columbite-tantalite series are associated with rare metal pegmatites...by-products of Tin-mining operations in central Namibia (Uis, Nainais, De Rust). Prominent niobium-tantalum...mineralised pegmatites occur in the Tantalite Valley in southern Namibia and have been mined for a long time |  | | Book | | Mountainland The Central Northern to Northwest Region including Damaraland The Central Namib Desertand...Copper Deposits The South The Pegmatitesin Central Namibia Luderitz and the Diamonds 44 49 241 254 272 275... Encyclopedia of the Mineralsof Namibia 443 Meteorites in Namibia Bibliography Index Photo credits...__ Republic of Namibia The President State House W°Ntdhoek FOREWORD Namibia is endowed with an...from near and far. Fine mineral specimen from Namibia are displayed in all the famous natural science |  | | Journal (article/letter/editorial) | | the Jos Plateau (Nigeria); Mn-rich columbite-tantalite is typical of the Alto Ligonha Province (Mozambique)...Shield (Egypt, Ethiopia) and the Tantalite Valley pegmatites (southern Namibia) and Large compositional variations...Nigeria and many pegmatites in the Damara Belt of Namibia. Trace element concentrations in CGM and other...Fetherston, 2004; Melcher et al., 2015). Central-East African countries have an almost 100-year-long history...tons of mixed Ta-Nb ore concentrate (columbite-tantalite, “coltan”, at about 30% Ta2O5) have been produced |  | | Book | | REPUBLIC OF NAMIBIA - MINISTRY OF MINES AND ENERGY GEOLOGICAL SURVEY THE MINERAL RESOURCES OF NAMIBIA FIRST...ENERGY Of the several hundred minerals present in Namibia, around sixty have been exploited. some, such as...base metals and industrial minerals have helped Namibia rank amongst the top five mining countries in Africa...terms of production and reserves. In this context, Namibia is a major producer of copper, lead, zinc, cadmium...unpublished. It is evident that mineral exploration in Namibia, as elsewhere. has changed from serendipitous discoveries |  | | Journal (article/letter/editorial) | | Mozambique belt in East Africa. Mozambique and Madagascar and within the Damara sequence in Namibia and morcovcr...Anihlvgonite-montehrasitc Pollucite Xcnotinic Columbite-tantalite Equatorial central and south Africa Beryl Cassiterite...Mommbique belt of East Africa, Mozambique, and Madagascar, and in the Damaran of Namibia (Figure 1). One...in Africa, is the Namaqualand-Gordonia-Kenhardt region or the Orange River pegmatite belt which is also...pegmatites vary to a great extent from one pegmatite region to another. In some areas lithium silicates are |  | Graupner, T., Melcher, F., Gäbler, H.-E., Sitnikova, M., Brätz, H., Bahr, A. (2010) Rare earth element geochemistry of columbite-group minerals: LA-ICP-MS data. Mineralogical Magazine, 74 (4) 691-713 doi:10.1180/minmag.2010.074.4.691 | Journal (article/letter/editorial) | | concentrations and distribution patterns of columbite-tantalite minerals from Ta-ore provinces worldwide are presented...K EY WORDS : LCT family pegmatites, columbite-tantalite, REE geochemistry, LA-ICP-MS data. Introduction...consideration (e.g. Rongi (Rwanda); Uis (Namibia); Rubikon (Namibia); Hagendorf (Germany)). References are...include: (1) the Homestead pegmatite, Tantalite Valley, Namaqualand, Namibia, Neoproterozoic (Kibaran) in age;...e.g. Černý, 1989, Fig. 1) using a columbite-tantalite quadrilateral. Three fields TABLE 1. Comparison |  | Melcher, Frank, Graupner, Torsten, Gäbler, Hans-Eike, Sitnikova, Maria, Henjes-Kunst, Friedhelm, Oberthür, Thomas, Gerdes, Axel, Dewaele, Stijn (2015) Tantalum–(niobium–tin) mineralisation in African pegmatites and rare metal granites: Constraints from Ta–Nb oxide mineralogy, geochemistry and U–Pb geochronology. Ore Geology Reviews, 64. 667-719 doi:10.1016/j.oregeorev.2013.09.003 | Journal (article/letter/editorial) | | Neoproterozoic (1000-542 Ma) TE 4.3.1. Kibara Belt (east-central Africa) 4.3.1.1. Radiometric data CE P...Zimbabwe) 4.3.3. Orange River Pegmatite Belt (Namibia, South Africa) AC 4.3.3.1. Radiometric data 4...Radiometric data 4.4.3.2. Mineralogy 4.4.4. Damara Belt (Namibia) 4.4.4.1. Radiometric data 2 ACCEPTED MANUSCRIPT...Mineralogy NU 5. Mineral chemistry of columbite-tantalite, tapiolite, wodginite and ixiolite in African...Alto-Ligonha Province (Mozambique) 5.4.4. Damara Belt (Namibia) 5.4.5. Older Granites (Nigeria) 5.4.6. Madagascar |  | Baldwin, J. R., Hill, P. G., Finch, A. A., von Knorring, O., Oliver, G. J. H. (2005) Microlite-manganotantalite exsolution lamellae: evidence from rare-metal pegmatite, Karibib, Namibia. Mineralogical Magazine, 69 (6) 917-935 doi:10.1180/0026461056960299 | Journal (article/letter/editorial) | | lamellae: evidence from rare-metal pegmatite, Karibib, Namibia J. R. BALDWIN1,*, P. G. HILL2, A. A. FINCH1, O...Ta-rich minerals. The intergrowth occurs within amblygonite/montebrasite nodules near the quartz core of...rare-metal Li/Be/Ta pegmatite at Rubicon, Karibib, Namibia. Electron microprobe analyses show that manganotantalite...replacement. Apatite is ubiquitous at the contact with amblygonite. The stability field of microlite may be extended...EY WORDS : ferrotapiolite, bismuth, apatite, amblygonite-montebrasite, subsolidus replacement. Introduction |  | | Book | | WINDHOEK ----------- MP mineral perspectives NAMIBIA This current report has been prepared by the Bureau...provide the latest available data and information on Namibia. Comments, revisions, and additional information... Thispublication hasbeencataloged asfollows: Namibia (Mineral pcrspecri vcs) Bibliography: p. 47-55...of Docs. no.: I 28.37/2: 1. Mineral indusrrics-Namibia. I. Coakley, George J. iI ! I l I I TN19... 45 47 Appendix.--Mineral 56 producers of Namibia•••••••••••••••••••••••••••••••••••••••• ILLUSTRATIONS |  | | Report (issue) | | Department of Industry and Resources 100 Plain Street EAST PERTH, WESTERN AUSTRALIA 6004 Telephone: (08) 9222...manganotantalite crystals from Moolyella, Pilbara region. Simpson Collection, Western Australian Museum............................................. 6 Tantalite minerals ................................................................................. 6 Tantalite indicators .................................................... 17 Spodumene, petalite, and amblygonite subtypes ................................... |  | | Journal (article/letter/editorial) | | giant K-Feldspar surrounded by red dendritic amblygonite in the Tanco pegmatite; right: Albite laths surrounded...granites is reviewed. Members of the columbite-tantalite group are the most common and economically important...1989). Especially the members of the columbite-tantalite, tapiolite, wodginite and ixiolite groups share...solution members of the orthorhombic columbite-tantalite group with the general formula AB2O6 (A = Fe2+...are columbite-(Fe), columbite-(Mn), tantalite-(Mn) and tantalite-(Fe). Their composition is traditionally |  | | Report (issue) | | Photograph by Gunnar Ries/CC-BY-SA-3.00. Right, a tantalite crystal. Photograph by Roger Weller, Cochise College...centimeter-size pyrochlore crystals from Uganda, and a tantalite crystal......................................... Tantalum is derived mostly from the mineral tantalite ((Fe,Mn)(Ta,Nb) 2O6 ), which is found as an accessory...suppliers of tantalum. Artisanal mining of columbite-tantalite (also called coltan) is practiced in many countries...resources, Australia, Asia, Russia and the Middle East, Africa, North America, and Europe. Identified niobium |  | | Report (issue) | | systems, such as the complex type (lepidolite, amblygonite, elbaite and danburite subtypes) beryl can be...microlite, more evolved members of the columbite-tantalite group, cookeite, tourmaline, lepidolite, topaz...topaz, a/bite, and quartz; 15 cm from the Shigar Valley, Skardu district, Northern Areas, Pakistan Because...nothing more of interest seemed to come out of the region until November 2002, when people from around Mandrosonoro...Madagascar to study some pegmatites in the Betafo region. Observing the exceptional tourmaline rough arriving |  | | Book | | metamict REE, Y, U-bearing phases. 3.1 Columbite-Tantalite Group The orthorhombic minerals of this group...miscibility gap from the tapiolite field. Columbite-tantalite is known in a disordered form (A,M 2h 4 0 8 (pseudo-oxiolite...heating at 1000°C. The alc ratio of columbite-tantalite was found a suitable order-disorder indicator...origin, and the structural state of columbite-tantalite from other parageneses is essentially unknown...~ ~ Fig.l. Compositiona1 ranges ofco1umbite-tantalite and tapio1ite minera1s in the co1umbite quadri1atera1 |  | | Journal (volume) | | Tertiary Alkaline Lavas from the Kahuzi- Biega Region, Western Rift, Kivu, Zaire: R. T. Lubala, A. B...England; B. D. Hackman, Nairobi, Kenya; P. J. Hamilton, East Kilbride, Scotland; C. J. Hawksworth, Milton Keynes...pseudotachylite and chert breccia (Paris 1985a). To the east, the Diepgezet sediments located above the T junction...cross cut by Malolotsha sediments which, to the east, have been folded along NE-SW axes. However, it...nicity ancJ continental evolution in the Barberton region, Transvaal. In Clifford, T. N. and Gass. I.G. (Eds) |  | | Report (issue) | | image. Lithium-brine evaporating ponds at Clayton Valley, Nevada. Lithium has many uses, the most prominent...massive sulfide, sedimentary exhalative, Mississippi Valley-type, and coal deposits and other types of deposits...production for the period 2006–10, by country or region and amount.......................................centimeter-size pyrochlore crystals from Uganda, and a tantalite crystal.........................................showing selenium concentrations in coal samples, by region of the United States.......................... |  | | Book | | systematically present the geology of each country, region and continent on Earth. Each book aims to provide...(Gariep Belt) cropping out in the western borders of Namibia and South Africa. They were split up in the Mesozoic...concerning the tectonic and geodynamic evolution of this region during the Precambrian. Major tectonometamorphic...tectonostratigraphic domains and structures of the region are presented, together with implications for the...domains are recognized: the Central Shield Zone in the east, and the Central Eburnean Zone and Lubango Zone |
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