| Oberthur, T., Weiser, T. W., Gast, L., Schoenberg, R., Davis, D. W. (2002) PLATINUM-GROUP MINERALS AND OTHER DETRITAL COMPONENTS IN THE KAROO-AGE SOMABULA GRAVELS, GWERU, ZIMBABWE. The Canadian Mineralogist, 40 (2) 435-456 doi:10.2113/gscanmin.40.2.435 | Journal (article/letter/editorial) | DETRITAL COMPONENTS IN THE KAROO-AGE SOMABULA GRAVELS, GWERU, ZIMBABWE THOMAS OBERTHÜR§ Bundesanstalt für...the Somabula gravels, a paleoplacer of Upper Karoo (Triassic, ~200 Ma) age near Gweru, Zimbabwe. The...The polymict spectrum of heavy minerals in the Somabula placers comprises staurolite, zircon, monazite,... columbite–tantalite, cassiterite, chromite, native gold, platinum-group minerals (PGM), and other components...derived from late Archean greenstone belts of the Zimbabwe craton. Keywords: zircon, monazite, tantalite | | | Journal (issue) | Geological Society of Zimbabwe G Z S Newsletter October 2015 No. 3 of 3 of 2015 Heavy mineral concentrate...concentrate (Total weight 4.974g) from the Somabula alluvial deposit. One diamond crystal (octahedron/dodecahedron)...alexandrite, sapphires, garnet, amethyst, topaz (“Somabula blue” and white), aquamarine, boart and native...Society of Zimbabwe, P.O. Box CY 1719, Causeway, Harare Geological Society of Zimbabwe Newsletter ... ARTICLES AND REPORTS A Review of Diamonds in Zimbabwe – a Century On .............................. | | | Journal (article/letter/editorial) | ancestry for the Somabula diamond-bearing alluvial deposit, Central Zimbabwe Andy Moore Somabula Explorations...Explorations (Pvt) Limited, Box CH399, Chisipite, Harare, Zimbabwe. e-mail: andy.moore@info.bw John Moore Geology...conglomerates, located to the southwest of Gweru in central Zimbabwe, have long presented an enigma in terms...Although conglomerate units occur throughout the Somabula Karoo succession, the diamonds and associated...20 km to the southwest of Gweru, in the Somabula district in central Zimbabwe (Figures 1 and 2). The diamonds | | | Journal (issue) | Geological Society of Zimbabwe Newsletter June, 2007 Geological Society of Zimbabwe Newsletter June 2007...SOCIETY OF ZIMBABWE, P.O. BOX CY 1719, CAUSEWAY, HARARE Geological Society of Zimbabwe Newsletter ...Department, University of Zimbabwe ………………………………………. 22 The Geological Survey of Zimbabwe …………………………………………………...…………………………………………………… …. 31 2 Geological Society of Zimbabwe Newsletter June, 2007 Editorial At last we have...collective predicament as geologists and miners in Zimbabwe, 2007. Let us take note and work towards solving | | | Journal (article/letter/editorial) | BRODERICK .\W^ D. PI.OWES 65 Landscape evolution in Zimbabwe from the Permian to present, with implications...Grahanistown. Somabula Explorations (Pvt.) Limited, Box CH399. Chisipite. Harare. Zimbabwe. e-mail: andy...Broderick 19 Jenkinson Road, Chisipite, Harare. Zimbabwe e-mail: makari@zol.co.zw D. Plowes 49 Arcadia...is presented to model drainage evolution -Acmss Zimbabwe since ihe Fenniiin. TÍii.s provides the framework...to the nortii and south oí' the modern central Zimbabwe watershed, wliich separates the Zambezi and Limpopo | | | Journal (article/letter/editorial) | between these trends. These resemble PGMs from chromite ores of the Krasnogorski intrusion (Kamchatka)...Os 92 D 16 4 Onoway Valley 4 Tulameen R. Somabula Karstovyi R. Makylgan 12 8 12 8 8 12 ...Composition fields: E Vilyui R. (n = 213) 20 Somabula Guli +R Rh 8 +R Rh 12 8 50 wt.% Bor Uryakh...Canada (Barkov et al., 2005) and Somabula gravels placer, Zimbabwe (Oberthür et al., 2002); E) full diagram...Valley, Canada (Cabri et al., 1996); Somabula gravels, Zimbabwe (Oberthür et al., 2002) and Guli massif | | Oberthur, T., Melcher, F., Gast, L., Wohrl, C., Lodziak, J. (2004) DETRITAL PLATINUM-GROUP MINERALS IN RIVERS DRAINING THE EASTERN BUSHVELD COMPLEX, SOUTH AFRICA. The Canadian Mineralogist, 42 (2) 563-582 doi:10.2113/gscanmin.42.2.563 | Journal (article/letter/editorial) | heavy-mineral concentrates mainly consist of grains of chromite and magnetite (95–99%), followed by grains of...heavy-mineral concentrates. Dark grey minerals are mainly chromite and magnetite. Sample SA 1016, Maandagshoek. All...stibiopalladinite or mertieite II. Base-metal sulfides, chromite and magnetite Very rare inclusions of base-metal...Although the concentrates contain numerous grains of chromite and magnetite, we found no intergrowths of the...from the Main Sulfide Zone of the Great Dyke in Zimbabwe (Oberthür et al. 1998, 2003, Oberthür 2002). In | | | Journal (article/letter/editorial) | mining for gold in the valleys of the J_ Cariboo district of British Columbia has led to a careful investigation...barriers of Glacial age. VII.—PLATINUM METALS IN THE SOMABULA DIAHONDIFEROTJS GBAVELSBr H. B. MAUFE. Southern...Geological Survey- Short Report No. 5, 1319. HE Somabula Diamondiferous Gravels which contain the diamond...composing the gravels revealed the presence of chromite and chromite-bearing rocks in appreciable quantity: and...occurrence of platinum in Southern Rhodesia, said: "The Somabula gravel for instance is a likely source, since | | | Journal (article/letter/editorial) | mining for gold in the valleys of the J_ Cariboo district of British Columbia has led to a careful investigation...barriers of Glacial age. VII.—PLATINUM METALS IN THE SOMABULA DIAHONDIFEROTJS GBAVELSBr H. B. MAUFE. Southern...Geological Survey- Short Report No. 5, 1319. HE Somabula Diamondiferous Gravels which contain the diamond...composing the gravels revealed the presence of chromite and chromite-bearing rocks in appreciable quantity: and...occurrence of platinum in Southern Rhodesia, said: "The Somabula gravel for instance is a likely source, since | | | Journal (article/letter/editorial) | The Somabula Forest Diamond Field Southern Rhodesia M. C. B The Somabula Forest diamond placers are...workings. The oldest mine of importance in the Somabula area is the Shamrock Gold Mine to the north of...for gold led to the discovery of diamonds on the Somabula Spruit in 1Ç)03 by H. R. Moir and his brother...other minerals associated with the diamonds at Somabula might be expected. PRODUCTION Value £27,843 3...331 2,991 2,230 3,083 1,917 GENERAL GEOLOGY The Somabula Forest and the surrounding country is underlain | | | Journal (article/letter/editorial) | mining for gold in the valleys of the J_ Cariboo district of British Columbia has led to a careful investigation...barriers of Glacial age. VII.—PLATINUM METALS IN THE SOMABULA DIAHONDIFEROTJS GBAVELSBr H. B. MAUFE. Southern...Geological Survey- Short Report No. 5, 1319. HE Somabula Diamondiferous Gravels which contain the diamond...composing the gravels revealed the presence of chromite and chromite-bearing rocks in appreciable quantity: and...occurrence of platinum in Southern Rhodesia, said: "The Somabula gravel for instance is a likely source, since | | | Journal (article/letter/editorial) | less than 10 lm, occasionally up to 100 lm) in chromite. The origin of coarse-grained PGM, in the form...extremely large IPGM grains (up to 1.3 mm) in chromite ores related to ophiolites was found to be approximately...than 10 lm, occasionally up to 100 lm) within chromite grains in many mafic–ultramafic complexes, including...have been described in the Somabula gravels of the Great Dyke in Zimbabwe, and detrital grains of Pt–Fe...different composition, and between hydrous fluids and chromite (Matveev and Ballhaus, 2002). A salient feature | | Barkov, A. Y., Martin, R. F., LeBarge, W., Fedortchouk, Y. (2008) Grains of Pt-Fe alloy and inclusions in a Pt-Fe alloy from Florence Creek, Yukon, Canada: evidence of mobility of Os in a Na-H2O-Cl-rich fluid. The Canadian Mineralogist, 46 (2) 343-360 doi:10.3749/canmin.46.2.343 | Journal (article/letter/editorial) | complexes. We suggest that a mineralized zone rich in chromite–magnesiochromite and hosted by an Alaskan–Uralian-type...Nous croyons qu’une zone minéralisée enrichie en chromite–magnésiochromite dans un complexe hôte de type...mineralized source-rock. Chromite–magnesiochromite from Florence Creek Nine grains of chromite (e.g., anal. 1,...alloy are related to a mineralized zone rich in chromite– magnesiochromite. Compositions of these grains...Barnes & Roeder 2001). Na-Rich Phases in PGM–Chromite Zones and Mantle Xenoliths The association of | | | Journal (article/letter/editorial) | reflecting high-temperature reaction involving chromite or magnesiochromite. The alloy grains from the...reflection of high-temperature reaction between chromite (or magnesiochromite) and a coexisting melt. As...reaction, Fe was strongly partitioned into the chromite phase, causing a strong increase in Mg/(Mg + Fe)...detrital components in the Karoo-age Somabula gravels, Gweru, Zimbabwe. Canadian Mineralogist, 40, 435–456 | | | Journal (article/letter/editorial) | Rifted, Craton, and Mobile-Belt Environments from Zimbabwe and Implications for Diamond Potential a Peter...Rifted, Craton, and Mobile-Belt Environments from Zimbabwe and Implications for Diamond Potential, International...Rifted, Craton, and Mobile-Belt Environments from Zimbabwe and Implications for Diamond Potential PETER R...tectonic settings illustrate the diamond potential of Zimbabwe. These are regions that kimberlites have intruded:...lithosphere lacking diamond potential. Introduction ZIMBABWE CURRENTLY IS a favored diamond exploration target | | | Journal (issue) | Geological Society of Zimbabwe Newsletter May 2006 Geological Society of Zimbabwe Newsletter May 2006...SOCIETY OF ZIMBABWE, P.O. BOX CY 1719, CAUSEWAY, HARARE Geological Society of Zimbabwe Newsletter ...4 Potential Exploitation of Great Dyke Eluvial Chromite...........................................................7 GEOLOGY DEPARTMENT, UNIVERSITY OF ZIMBABWE ...................................................................7 THE GEOLOGICAL SURVEY OF ZIMBABWE ………………………………………………………… 8 RECENT EARTHQUAKE ACTIVITY | | | Report (issue) | interest in the geo logy and mineral resources of Zimbabwe which followed the removal of United Nations sanctions...original Bulletin is the insertion of Table IIIA, Zimbabwe Mineral Production and Value, on page 114A. Due...and thrusts add to the complexity. Remnants of chromite-bearing rocks preserved in the granite on the...contains large reserves of high-grade metallurgical chromite. Resting on these rocks with distinct erosional...involved in the nappe. The conglomerate contains chromite pebbles and was regarded as the base of the Bulawayan | | Oberthur, T., Weiser, T. W., Melcher, F., Gast, L., Wohrl, C. (2013) DETRITAL PLATINUM-GROUP MINERALS IN RIVERS DRAINING THE GREAT DYKE, ZIMBABWE. The Canadian Mineralogist, 51 (2) 197-222 doi:10.3749/canmin.51.2.197 | Journal (article/letter/editorial) | PLATINUM-GROUP MINERALS IN RIVERS DRAINING THE GREAT DYKE, ZIMBABWE Thomas OBERTHÜR§, Thorolf W. WEISER, Frank MELCHER...and PGE-oxides (unstable). Keywords: Great Dyke, Zimbabwe, alluvial sediments, Pt-Fe alloy, Os-Ir-Ru alloy...Bushveld Complex of South Africa, the Sudbury district in Canada, and later Norilsk in Russia came into...intrusions (Bushveld, South Africa; Great Dyke, Zimbabwe; Stillwater, USA) that host the overwhelming proportion...of knowledge on the Great Dyke of Zimbabwe. The Great Dyke of Zimbabwe constitutes the world’s second largest | | Barkov, A. Y., Martin, R. F., Fleet, M. E., Nixon, G. T., Levson, V. M. (2008) New data on associations of platinum-group minerals in placer deposits of British Columbia, Canada. Mineralogy and Petrology, 92 (1) 9-29 doi:10.1007/s00710-007-0192-6 | Journal (article/letter/editorial) | alluvial placer along the Swift River): almandine, chromite, staurolite, pyrite, diopside, scheelite and goethite;...Creek): hematite, almandine, epidote, staurolite, chromite, kyanite, scheelite, pyrite, rutile, galena, spinel...Quesnel River): almandine, hematite, pyrite, barite, chromite, olivine, diopside, rutile, chalcopyrite, galena...goethite, hematite, diopside, pyrite, barite, chromite and chalcopyrite; sample VLE-200169a (low terrace...terrace placer on Wilson Creek): goethite, chromite and epidote; sample VLE-2001-70b (deep paleochannel | | | Journal (article/letter/editorial) | Archaean Mashaba Igneous Complex, south-central Zimbabwe M.D. Prendergast Guesachan, Shielhill Road, Kirriemuir...fields are conspicuous greenstone components of the Zimbabwe craton and host important mineral deposits. Sills...preserved examples of a komatiitic sill in the Zimbabwe craton and contains important deposits of chrysotile... 1968; Anhauesser, 1986; Laubscher, 1986) and chromite (e.g. Prince mine: Wilson, 1968; Wilson and Nutt...komatiitic flow fields in different parts of the Zimbabwe craton (Wilson, 1979, Wilson et al., 1995; Prendergast | | | Journal (issue) | Geological Society of Zimbabwe Newsletter June, 2010 Geological Society of Zimbabwe G Z S Newsletter...SOCIETY OF ZIMBABWE, P.O. BOX CY 1719, CAUSEWAY, HARARE Geological Society of Zimbabwe Newsletter ...for 2009 ……………………………………… Landscape Evolution in Zimbabwe from the Permian to present, with implications...……………….. 16 Geology Department, University of Zimbabwe ……………………………………… 16 Geological Survey Department...………………………………………………… 25 2 Geological Society of Zimbabwe Newsletter June, 2010 Editorial As we present | | | Journal (article/letter/editorial) | few of the intensely sheared rocks of such a district, except very locally--a few yards, for instance...Rifle Kopje, near Bulawayo; Red Hills, Victoria district). In other cases they occur as well-marked dykes...sequence. I t is in the somewhat remote Lomagundi district that these beds have attracted most attention...beds in the course of two lengthy visits to the district, and have recently paid i I have to express my...present day, which are intrusive. In the Abercorn district, also in Northern ]Kashonaland, and possibly on | | | Journal (article/letter/editorial) | Evidence from the rivers draining The Great Dyke in Zimbabwe (Oberthür et al., 2013) provides a view of the...the formation of oxidised PGM. The Great Dyke, Zimbabwe (Locmelis et al., 2010) and the Aguablanca deposit...the Main Sulphide Zone (MSZ) of the Great Dyke, Zimbabwe. Large Pt-Fe aggregates do occur in the rocks...minerals found in the alluvial nuggets such as 19 chromite, silicates, sulphides or composite glass-silicate...South Africa, Melcher et al., 2005; Great Dyke, Zimbabwe, Oberthür et al., 2002, 2003, 2013; Uktus, Central | | Stribrny, B., Wellmer, F. -W., Burgath, K. -P., Oberthür, T., Tarkian, M., Pfeiffer, T. (2000) Unconventional PGE occurrences and PGE mineralization in the Great Dyke: metallogenic and economic aspects. Mineralium Deposita, 35 (2) 260-280 doi:10.1007/s001260050019 | Journal (article/letter/editorial) | initial production from mines in the Great Dyke of Zimbabwe has yielded 2.1 t Pt. The remaining 9.54 t are...Russia Stillwater, USA Sudbury, Canada Great Dyke, Zimbabwe Kupferschiefer, Poland Bregu i Bibes, Albania...production, for example those of the Great Dyke, Zimbabwe, ± potential alternatives in the form of unconventional...mineralizations PGE in layered intrusions: the Great Dyke, Zimbabwe Geological setting The ca. 2.58-Ga-old Great Dyke...cuts Archean granites and greenstone belts of the Zimbabwe craton (Worst 1960). In its present level of erosion | | | Journal (article/letter/editorial) | collected from the O’Donnel River in the Atlin Mining District, approximately 32 km southeast of the community...east of the town of Quesnel in the Cariboo Mining District. The analyzed sample is a light brown, moderately...re-equilibration between the “Pt2Fe” alloy and a coexisting chromite or magnetite. However, the corresponding depletion...a Pt3Fe-type alloy in the rim, enclosed within chromite in the Tulameen complex (Nixon et al. 1990). The...depleted in Cr, which is thus consistent with a chromite-rich source. The characteristic association between |
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