 | | Book | | Koffiefontein 2. Smaller mineralised kimberlites in South Africa 2.1 The Oaks 2.2 The Zebediela Kimberlites 2.3...Lower Vaal and Middle Orange River 3.3 Bushmanland 3.4 The Lower Orange River 3.5 West Coast Onshore...their relative production contributions in South Africa were, primary (kimberlite) 8.63 million carats...significantly diamondiferous lamproites are known in South Africa where the primary sources mined are kimberlite...ultramafic rocks, including xenocrysts such as pyrope garnet, picro-ilmenite, chromian spinel and chrome-diopside |  | | Book (volume) | | DIAMOND-BEARING ALLUVIAL GRAVELS OF THE UNION OF SOUTH AFRICA DIAMOND-BEARING GRAVELS DRAINAGE WEATHERING TRANSPORTATION...ALLUVIAL DIAMONDS THE SOUTH-WEST AFRICA DIAMOND DEPOSITS THE VAAL RIVER ALLUVIAL GRAVELS THE DIAMOND-BEARING...OCTAHEDRON CONTACT TwINS RAisEo MARINE GRAVEL TERRACE RIVER AT THE MoUTH OP THE OLIPHANT's 202. 202. 203....KIMBERLITE, TANGANYIKA TERRITORY SINK-HoLE, HoLFONTEIN RIVER GRAVELS RESTING ON WHITE CLAY GRAVEL TERRACE AT...MOUTH OF THE ORANGE RIVER - 208. CROSS-SECTION, MERENSKY GRAVELS 209. RoorwAL 209. RIVER TERRACES, NEAR |  | | Journal (article/letter/editorial) | | hiddenite, kornerupine, kunzite, kyanite, peridote, pyrope, rhodolite, spessartine, (chrome) titanite, spinel...Grossular (hessonite, tsavorite), spessartine, pyrope and its variety rhodolite, andradite (demantoid)...at Blind River-Elliot Lake,placers Canada,and and paleoplacers. Witwatersrand, Modern Africa occur in...Middle alteration. The conglomerates at(1900 Blind River-Elliot Canada, and Witwatersrand, South Proterozoic...World-classLake, deposits are at Witwatersrand, South Africa occur in stratigraphic series thatdodeveloped when |  | | Book | | fields in Brazil 7 1.3 Kimberlite fields in South Africa 8 1.4 Major kimberlite sites in Russia 9 1.5...during formation of kimberlites of the diamond and pyrope subfacies 92 6.4 Model of idealized kimberlite...epiclastic facies of kimberlites in central and southern Africa 104 6.11 Lesotho dike swarm 107 6.12 Vertical...marine placers in southwest Africa 150 8.2 The drainage area of Orange River through major kimberlite...kimberlite fields of South Africa 151 8.3 Size decrease of diamonds recovered from beach sands from the mouth |  | | Journal (article/letter/editorial) | | ABTICLES. I.—ON THE DIAMOND F I E L D S OP SOUTH AFRICA. By T. RTJPEKT JONES, F.G.S., Professor of Geology...DIAMOND BEGION.—The diamond-bearing region in South Africa, as at present known, is chiefly within the valley...the Vet); but it is known also to extend down the Orange (Gariep) Valley for a few miles after the junction...diamonds, at several places, on both sides of the river, at Hebron, Klipdrift (near Pniel), Zitzikamma,...Litkatlong), etc.; and on the south side of tiie Orange Eiver, they have been found some miles north-west |  | | Book | | fruitful collaboration. Much of my fieldwork in southern Africa has been carried out with the cooperation and...7.3 2.8 2.9 Africa . . . . . . . . . . . . . . . . . . . . . . . . . . . . West Africa . . . . . . .... . . . . Central Africa. . . . . . . . . . . . . . . . . . . . . . . East Africa. . . . . . . . . .... . . . . . . . . . . . . . . . Southern Africa . . . . . . . . . . . . . . . . . . . . . U.S.S.R. . ...playing on the banks of the Orange River near Hopetown, Cape Province, South Africa, found a beautiful, white |  | | Journal (article/letter/editorial) | | andtheDevelopment of DiamondPlacers in Western South Africa M. C. J. DEWIT{ De BeersConsolidated Mines,Geology...thedevelopment of diamond placers alongthewestcoastof southern Africa.The evolution ofthedrainage systems thatdeveloped...andmorenortherly system, alsoknownas the Kalahari River,drained southernBotswanaand Namibia and entered...centralSouthAfricaweretransported by the Karoo River to the coast. ByearlyCenozoic times,thelowerKa...thepaleo-Caruarvon Leegte joinedasthepaleo-Hartbees River--another majortributary oftheOrange inthe Plio-Pleistoeene |  | DE WIT, M.C.J., WARD, J.D., BAMFORD, M.K., ROBERTS, M.J. (2009) THE SIGNIFICANCE OF THE CRETACEOUS DIAMONDIFEROUS GRAVEL DEPOSIT AT MAHURA MUTHLA, NORTHERN CAPE PROVINCE, SOUTH AFRICA. South African Journal of Geology, 112 (2) 89-108 doi:10.2113/gssajg.112.2.89 | Journal (article/letter/editorial) | | AT MAHURA MUTHLA, NORTHERN CAPE PROVINCE, SOUTH AFRICA M.C.J. DE WIT Department of Geology, University...0002, South Africa e-mail: deWit@icon.co.za J.D. WARD 17 Buitekring, Stellenbosch, South Africa e-mail:... Private Bag 3, Johannesburg, WITS 2050, South Africa e-mail: marion.bamford@wits.ac.za M.J. ROBERTS...South Africa e-mail: mike.roberts@debeersgroup.com © 2009 June Geological Society of South Africa ABSTRACT...believed to have been wetter in the interior of southern Africa. In addition to the diamonds, other kimberlite |  | | Journal (issue) | | gemological Properties of Chatham Flux-Grown Synthetic orange Sapphire and Synthetic Blue Sapphire," by Robert...professor at the University of Stellenbosch, South Africa. Dr. Giibelin was born in Lucerne and completed...Elandesfontein, near Pretoria, Republic of South Africa. The stone was of unusually fine color and purity...was found in the Premier Mine, Republic of South Africa, in 1954. At the time, the late Sir Ernest Oppenheimer...found. It was discovered in 1938 in the San Antonio River, municipality of Coromandel, Minas Gerais, Brazil |  | | Book (edition) | | Burma. gemstones. Tanzania. Rare Sri Lankan orange sapphire of 57.26 carats. Emerald crystal, associated...Renaissance pendant set with Colombian emeralds Africa, Australia and Siberia. Magnificent Colombian...Iridescent labradorite P) 10 The Great Star of Africa (Cullinan I), set in the Sceptre with the Cross...malachite, manganese the pink of rhodonite and orange of spessartine garnet. In most gems these metallic...or cross cut 30 Styles of cutting d,e,f Table (orange), bezel facets (pink) and pavilion main facets |  | | Journal (article/letter/editorial) | | Worldwide Localities of Diamonds Thomas Moore 5755 East River Road, #1317 Tucson, AZ 85750 Natural diamond crystals...from the Brazils, particularly from the bed of the river Jigitonhonha” [=Jequitinhonha]. Mineralogical Record...collected in Brazil (probably in the Jequitinhonha River area) by the British mineral dealer John Mawe and...Venice, and a southern 11 Figure 4. A diamond crystal in “blue ground” from South Africa, probably from...until the first decades of the 20th century. South Africa is still a significant producer, but since about |  | Van Schijndel, Valby, Cornell, David H., Anczkiewicz, Robert, Scherstén, Anders (2020) Evidence for Mesoproterozoic collision, deep burial and rapid exhumation of garbenschiefer in the Namaqua Front, South Africa. Geoscience Frontiers, 11 (2) 511-531 doi:10.1016/j.gsf.2019.06.004 | Journal (article/letter/editorial) | | exhumation of garbenschiefer in the Namaqua Front, South Africa Valby Van Schijndel a, 1, David H. Cornell a, b...Stellenbosch, Private Bag X1, Matieland, 7602, South Africa Institute of Geological Sciences, Polish Academy...exhumation of garbenschiefer in the Namaqua Front, South Africa, Geoscience Frontiers, https://doi.org/10.1016/j...Terrane of the Namaqua-Natal Province of South Africa (Fig. 1) form part of an NW-vergent foreland thrust...Namaqua sector of the Namaqua-Natal province, South Africa. BoSZ: Boven Rugzeer shear zone, BSZ: Brakbosch |  | | Journal (article/letter/editorial) | | were obtained from alluvial mines along the Orange River close to Oranjemund, as well as from all the...oxygen ions. The nominal Diamonds Single inclusions Pyrope garnet Orthopyroxene Mg-chromite Olivine Clinopyroxene...depletion in Ca has previously only been observed in pyrope garnet inclusions from the Kaapvaal block (Finsch...McDade and Harris, 1999) and the Limpopo belt (River Ranch, Olivine (22 inclusions from 21 diamonds)...diffusion coefficients for Ce, Sm. Dy and Yb in pyrope garnet at a pressure of 2.8 GPa and temperatures |  | | Journal (article/letter/editorial) | | Rondebosch 7701, South Africa b Council for Geoscience, P.O. Box 572, Bellville, South Africa Abstract The newly...orogenesis is invariably preceded by subduction. In southern Africa, the assembly of 6 the Gondwana supercontinent...preserved accretionary metamorphic signal in most 14 southern African Pan-African belts has contributed to reconstructions...first place. 21 Along the west coast of southern Africa, the southward-younging Kaoko, Gariep and Salda-...accretionary metamorphic signature in its Southern and Southern Marginal Zones that bound 30 the Kalahari |  | | Journal (issue) | | Marine Mining of Diamonds Off the West Coast of Southern Africa John 1. Gurney, Alfred A. Levinson, and H ...have been identified off the western coast of southern Africa. The lead article in this issue examines the...gem-qnality diamonds exists off the west coast of southern Africa. Over the course of millions of years, many...many diamond-bearing kimberlite pipes in the Orange River drainage basin have been extensively eroded and...Gsocftemsfry, Universityof c47e Town, flOrtdabOSCh, Soufft Africa. and ateo Chairman ofBenguela ConcessionsPm).~ |  | | Journal (article/letter/editorial) | | Craton; Kaapvaal Craton; Lithospheric mantle; Cr-pyrope garnets; Seismic tomography; Kimberlites 1. Introduction...translithospheric, and that Fig. 1. Structural units of southern Africa, as discussed in this paper, superimposed on...use these xenocryst suites, including >3500 Cr-pyrope garnets from >50 kimberlites (Fig. 2), to examine...alluvial deposits of local derivation; over 3400 Cr-pyrope garnets from more than 50 localities have been...Geochemical information from garnets The Y content of Cr-pyrope garnets is a measure of depletion (Griffin and |  | | Book (edition) | | names, particularly those of the new republics of Africa and Asia, has caused problems. Where possible these...intermediate and acid members of the volcanic province in southern Brazil and Uruguay, and the fire opals occurring...Such rocks were first found in Kimberley, South Africa, and because they did not resemble any currently...have been found subsequently in other parts of Africa, Siberia (Figure 1.11), India, Figure 1.11 Diamond...perhaps in a river system, the resulting deposits are called alluvial. In the headwaters of a river system |  | | Journal (issue) | | from Riemvasmaak, Northern Cape Province, South Africa . . . . . . . . . . . . . . . . ...of minutes! Specimens of habit 4 fluoresce pale orange in both shortwave and longwave ultraviolet light...lakebed would have to be removed, as would the river which fed the lake, and the provincial road which...emplaced during that period. The asbestos deposits of southern Québec are situated in a zone of mafic and ultramafic...recently. Moreover, the mine has yielded good, gemmy orange grossular crystals, paler than similar crystals |  | | Journal (article/letter/editorial) | | fresh-broken, subangular, and rounded. Garnet, including Pyrope and Cinnamon-stone, very abundant; fresh and subangular...A piece of Ostrich egg-shell. No. 17. On the Orange River, thirty-s~ mil~ below H O l ~ n . [Probably...informsme that he has ob/~neclmore specimens from this river, like those of the Vaal gravel, and that he is informed...EXPLANATION OF PLATE I. Map of the Vaal River from Plant Berg to the Reit River. 3. 6~t ~he GEOL06Y of the DIA~OI~D-FrELDS...DIA~OI~D-FrELDS of SOVTH AFRICA. By Dr. J o ~ Saxw, Colesberg, Cape Colony. (Communicated by Dr. |  | | Journal (article/letter/editorial) | | of yellow, brown, and white and, less commonly, orange, pink, green, blue, red (fig. 2), and black. Famous...canary-yellow Cape Diamond (I67 carats, uncut), and the orange-yellow Tiffany Diamond ( I 28 carats). Diamond’s...graphite. magnetite, ilmenite, garnet (usually pyrope). chrome-diopside, chlorite, biotite, phlogopite...carats; Star of Sierra Leone. 969 carats; Woyie River, 770 carats; President Vargas, 727 carats; Jonker...found at discovery of individual diamonds in the southern the most productive of Appalachians, generally |  | | Book (edition) | | chemical conditions necessary for gem formation pyrope garnets and rare green chrome diopsides. topaz... granite 20 pressures in subduction zones. 9 Pyrope garnet and diamond form in the mantle. 10 Gem minerals...minerals into the soil. 15 Gem minerals accumulate in river gravels. 16 Jadeite boulders accumulate in rivers...crystallize as pegmatite (3) and form the most southern Thailand. Once at the surface, important source...pipe-like bodies of kimberlite or lamproite rock, or in river and beach gravels, where they accumulate after erosion |  | | Journal (article/letter/editorial) | | a Mesoproterozoic continental back-arc in southern Africa Julia Bial a , Steffen H. Büttner b,∗ , Volker...University, P.O. Box 94, Grahamstown 6140, South Africa a r t i c l e i n f o Article history: Received...along the southern and western margins of the Achaean Kaapvaal Craton and stretches from southern Namibia...Namibia into northwestern South Africa and, under Phanerozoic cover, further to the KwaZulu Natal Province...Province at the south-east coast of South Africa. The Namaqua-Natal Province is a low-pressure amphibolite to |  | | Report (issue) | | Kingdom . . . ... . .. (1922) Part II. Britisl1 Africa . .. . ,. . .. (1922) Par~ III. Britisl1 America...and New Zealand .. . (1922J Part VI. Europe and Africa (I!"oreign) ~ .. . (1922) Part VII. Foreign Arueriea...Sierra Leone • • • • • • • • Southern Rhodesia ••• •• • South~West Africa Tenitory Tanganyika Territory...Territory ••• Union of South Africa ..Canada ••• ••• ••• •• • Newfoundland • • • • •• ••• British Guiana • ••... • •• ••• ••• ... ... • •• French \Vest Africa Madagascar • •• • • •• 96 • •• ••• • •• |  | | Book (edition) | | Gemstones of Southern Africa a Collector’s Guide ■ Rocks, Minerals and Gemstones of Southern Africa & —...— - T ~ '' .rats en&nes L of Southern Africa A Collector’s Guide - Struik Publishers (an operating...suggestions and advice. Author’s Preface Southern Africa has much to offer the amateur geologist, whatever...the North-West Cape; and at Goodhousc on the Orange River cast of Vioolsdrif. In Namibia amethyst can...also to citrine, a yellow quartz rare in South Africa. True topaz can be distinguished from any quartz |  | | Book | | magma as a whole. Diamondiferous pipes in South Africa and elsewhere contain this kind of rock. When these...crystals of magmatic (igneous) origin such as olivine, pyrope and diopside in diamond. Pegmatite minerals such...formation cannot occur in a host from another; pyrope which is formed at great depths and high pressures...contain liquid inclusions. Neither do diamond and pyrope which have crystallized at great depths and at...yellow, orange, red and purple and may be 0.5 mm or larger. Some, mostly chromium-rich pyrope garnets |
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