 | | Book | | Phase 5. Sample Treatment D) World Production E) South African Diamond Occurrences 1. Large Kimberlite...Koffiefontein 2. Smaller mineralised kimberlites in South Africa 2.1 The Oaks 2.2 The Zebediela Kimberlites 2... their relative production contributions in South Africa were, primary (kimberlite) 8.63 million carats...Premier mine. The proportion of gems in the West Coast marine deposits is over 98%. The MIBA mine in the...the Congo and the Argyle mine in Australia have an average gem content of only 5%. The dispersal of diamonds |  | | Journal (article/letter/editorial) | | Ultramafic nodules from the Kimberley pipes, South Africa F. R. BOYD Geophysical Laboratory, Carnegie...collected in a number of other areas in southern Africa in two important respects: (1) There are no sheared...mosaic-porphyroclastic. In most nodule suites from southern Africa and elsewhere in the world, these low-temperature...low-temperature. mainly coarse peridotite xenoliths from northern Lesotho and other areas. Abundant sheared dunites...Eclogites and glimmerites (granular or sheared phlogopite-rich nodules; DAWSON and Slmr~, 1977), and amphibolites |  | | Journal (article/letter/editorial) | | Kimberlite-hosted diamond deposits of southern Africa: A review Matthew Field a,⁎, Johann Stiefenhofer...Southdale, 2135, South Africa c De Beers Group Services, PO Box 47, Kimberley, South Africa d De Beers Canada...discovery of diamonds in river deposits in central South Africa in the mid nineteenth century, it was at Kimberley...economic and industrial development of southern Africa. Following the discoveries at Kimberley, even more...more valuable deposits were discovered in South Africa and Botswana in particular, but also in Lesotho |  | | Journal (article/letter/editorial) | | Geological Sciences, University of Cape Town, Rondebosch 7700, South Africa e-mail: David.R.Bell@asu.edu ...University of Cape Town, Rondebosch 7700, South Africa Email: © 2004 Geological Society of South Africa ABSTRACT...subcontinental lithospheric mantle of southern Africa, and may be used to probe its compositional structure...garnet megacrysts from 61 kimberlites in southern Africa define four broad arrays on the basis of Cr2O3...mantle. High-Cr megacrysts in kimberlites of the northern cratonic areas bear the influence of lithospheric |  | | Book | | Mitchell, A. Nicolas, D.J. Powell, A.M. Reid, J.V. Smith, N.V. Sobolev, W.E. Stephens, and P.J. Wyllie. In...John Gurney and Joe Smith with whose research groups at the universities of Cape Town and Chicago I have...collaboration. Much of my fieldwork in southern Africa has been carried out with the cooperation and assistance...7.3 2.8 2.9 Africa . . . . . . . . . . . . . . . . . . . . . . . . . . . . West Africa . . . . . . .... . . . . Central Africa. . . . . . . . . . . . . . . . . . . . . . . East Africa. . . . . . . . . . |  | | Journal (article/letter/editorial) | | SPINEL MACROCRYSTS FROM KIMBERLITES IN SOUTHERN AFRICA DANIEL J. SCHULZE§ Department of Geology, University...single-crystal macrocrysts in kimberlites from southern Africa (approximately 1500 grains from 20 kimberlites...from a variety of mantle xenoliths from southern Africa and North America (approximately 150 xenoliths)...partitioned into a different phase, such as metasomatic phlogopite. Such Cr-rich macrocrysts are more common in...Unusually Fe- and Ni-rich macrocrysts unique to the Lace mine are from Fe-rich orthopyroxene-bearing peridotites |  | | Book (volume) | | S. R. Hart, I. D. MacGregor, R. H. Mitchell, D. Smith, J. Ro Smyth, H. Go Wilshire The MantleSample...development since the First Kimberlite Conference, held in Cape Town in 1973, has come in the interpretation of...Diamond-Graphite Ecologite From the Roberts Victor Mine, C. J. Hatton and John J. Gurney .................Granulites and Eclogites From Lesotho, Southern Africa, W. L. Griffin, D. A. Carswell, and P. H. Nixon...Garnet Harzburgite XenolithsFrom the Premier Mine, South Africa, R. V. Danchin ........................ |  | | Book (volume) | | rise and development of the diamond mines of South Africa, from an historical, economic and technical...collect during my many visits to all parts of South Africa where kimberlite deposits occurred and the filing...was necessary to file * "The Diamond Mines of South Africa," by Gardner F. Williams. V . Vl l I I...my attention from the time of my arrival in South Africa was the accidental and cognate inclusions found...had collected specimens from various parts of South Africa for years, it has only been since the publication |  | | Journal (article/letter/editorial) | | and that Fig. 1. Structural units of southern Africa, as discussed in this paper, superimposed on a...from kimberlites and some alluvial deposits of local derivation; over 3400 Cr-pyrope garnets from more...temperature for each grain can be referred to a local paleogeotherm to estimate the depth from which the...P – T estimates for garnet suites from southern Africa. The Garnet Geotherm (Ryan et al., 1996) is shown...Fig. 4. Y vs. TNi for garnet suites from southern Africa. Thick dashed lines mark the approximate upper |  | | Journal (article/letter/editorial) | | mineral in many Group I kimberlites (defined by Smith 1983), occurring in a variety of different associations...kimberlites (e.g. Monastery (Gurney et al. 1979) and Frank Smith (Pasteris et al. 1979)). These large grains are...pyroxene-ilmenite xenolith from the Weltevreden mine, which they suggest is also genetically related...lamellar intergrowths with pyroxenes in the Frank Smith kimberlite (Pasteris et al. 1979). In contrast...ilmenites from the Mayeng Kimberlite Sills, South Africa (adapted from Apter et al. 1984). Solid circles |  | | Journal (article/letter/editorial) | | FRACTIONS AND WHOLEROCK SAMPLES J.D. KRAMERS and C.B. SMITH Department of Geology, University of Zimbabwe, Harare...University of the Witwatersrand, Johannesburg 2001 (South Africa) (Received April 5, 1982; revised and accepted...November 19, 1982) ABSTRACT Kramers, J.D. and Smith, C.B., 1983. A feasibility study of U-Pb and Pb-Pb..." o ! 5 00 ! Fig. 1. Sketch map of southern Africa with localities of pipes studied (1 = Kimberley...1.1. Kimberlite pipes in Kimberley (Cape Province, South Africa): Wesselton, Dutoitspan, Bultfontein |  | | Book | | Hawthorne, Bram Janse, Mal McCallum, Barbara Scott Smith, Simon Shee, Mike Skinner, Bruce Wyatt, and Peter............................... 126 5.3.3.2. West Africa ........................................... 126.... . . . . . . . . . . . . . . . . . . . 6.6. Phlogopite . . . . . . . . . . . . . . . . . . . . . . ...Macrocryst Phlogopite (Paragenesis 1) ..................... 6.6.2. Groundmass/Microphenocryst Phlogopite (Paragenesis...15. 6.6.3 .1. Diverse South African Kimberlites (Dawson and Smith 1975, Smith et al. 1978) . . . . . |  | | Journal (article/letter/editorial) | | metamorphism, and metasomatism: The complex history of South African upper-mantle symplectites Stephen W. Field*...clinopyroxene, pyrope garnet, Mg-rich amphibole, and phlogopite, are common in depleted peridotites recovered...symplectites. Symplectites containing amphibole and phlogopite are pyroxene + spinel ± garnet symplectites that...are found in the Horoman peridotite complex in northern Japan (Takahashi and Arai 1989), in ultramafic...recovered from mafic lavas in the American southwest (Smith 2000), and in xenoliths found in Siberian kimberlites |  | Graham, S., Lambert, D.D., Shee, S.R., Pearson, N.J. (2002) Juvenile lithospheric mantle enrichment and the formation of alkaline ultramafic magma sources: Re–Os, Lu–Hf and Sm–Nd isotopic systematics of the Norseman melnoites, Western Australia. Chemical Geology, 186 (3) 215-233 doi:10.1016/s0009-2541(01)00408-9 | Journal (article/letter/editorial) | | Exploration Australia Limited, 60 Wilson Street, South Yarra, Victoria 3141, Australia c Australian Research...source. Compositions of whole rocks and groundmass phlogopite and clinopyroxene show that although these rocks...the lithospheric and asthenospheric mantles. Phlogopite is ubiquitous in alkaline ultramafic rocks, but...concentrations of the incompatible elements (e.g. Smith et al., 1985; Carlson et al., 1996; McDonald et...sub-lithospheric mantle source (Ailbert et al., 1983; Smith, 1983; Nelson, 1989, Nelson et al., 1988; Nowell |  | | Journal (article/letter/editorial) | | from 16 intrusions in Lesotho, the Republic of South Africa, and Tanzania have been investigated. The following...bronzite that are found in the kimberlites of northern Lesotho also show some fractures and cracks (NlxoN...the abundance of zircon in the Kimberley and Frank Smith mines, he admitted that zircon may possibly be...intergrowths are particularly common at Monastery mine (WHITELOCK 1973). Among the inclusions in zircon...1973b) found diamond, magnesian ilmenite and phlogopite in the zircons from Kao and Monastery mines. |  | | Journal (article/letter/editorial) | | pyroxenites from the Gansfontein kimberlite, South Africa: Evidence for megacryst magma – mantle interaction...University of Cape Town, Rondebosch 7700, South Africa P.O. Box 31316, Tokai 7966, South Africa e-mail: geo-odyssey@ananzi...Geological Sciences, University of Cape Town, Rondebosch 7700, South Africa Department of Geological Sciences...Geological Sciences, University of Cape Town, Rondebosch 7700, South Africa e-mail: aleroex@geology.uct.ac...ac.za © 2004 Geological Society of South Africa ABSTRACT The Gansfontein kimberlite contains a suite |  | | Journal (article/letter/editorial) | | understand the nature of the upper mantle in southern Africa and the processes that have modified it, including...within or near the Kaapvaal craton 1 of southern Africa (Figure 1) and it is the study of the geological...ultradepleted nod ules have been described from northern Lesotho (Carswell et a11979) but they are much...documented from northern Lesotho (Nixon & Boyd 1973b), Jagersfontein (MacGregor 1975), and Frank Smith '(Boyd...harzburgite nodules from kimberJites in southern Africa. Pyrolite quoted from Ringwood (1975). Table 1 |  | | Journal (article/letter/editorial) | | aluminum-rich silicate minerals such as olivine and phlogopite in kimberlites, or pyroxene and plagioclase in...where the crystallization of spinel affects the local environment ahead of the growing spinel crystal...kimberlites into Groups I and II (Dawson, 1967; Smith, 1983). Mitchell (1986, 1995) has described the...slightly lower content of potassium and much less phlogopite, and a higher content of groundmass oxide minerals...zoning and also on atoll-spinel formation. Very local conditions such as nucleation, or lack of nucleation |  | | Journal (article/letter/editorial) | | metasomatised and show the introduction of metasomatic phlogopite, clinopyroxene and ilmenite. The petrography...Geology, Rhodes University, Grahamstown, 6140, South Africa K.S. Viljoen (&)1 Bernard Price Institute of...Witwatersrand, Private Bag 3, WITS, Johannesburg, 2050, South Africa 1 Present address: Anglo American Research Laboratories...Laboratories (Pty) Ltd P.O. Box 106, Crown Mines, 2025, South Africa Fax: 27-11-4961758, E-Mail: kimres@is.co.za...upper mantle beneath the Kaapvaal craton in South Africa using petrological, geochemical and isotope |  | | Journal (article/letter/editorial) | | Geology, Rhodes University, Grahamstown, 6140, South Africa b c SC R a School of Earth and Ocean Sciences...These typical chemical trends are illustrated for South African Group I and Group II kimberlites in Figs...kimberlite from the Kaapvaal Craton in southern Africa, the off-craton MA Gibeon kimberlites in Namibia...garnet, up to 15 mm in diameter, together with phlogopite laths, generally 1-2mm, though more rarely up...extinction and occasionally kink bending. Scott-Smith et al. (2013) propose that kimberlitic olivines |  | | Book (volume) | | DIAMOND-BEARING ALLUVIAL GRAVELS OF THE UNION OF SOUTH AFRICA DIAMOND-BEARING GRAVELS DRAINAGE WEATHERING...SYSTEMS THE ORIGIN OF THE ALLUVIAL DIAMONDS THE SOUTH-WEST AFRICA DIAMOND DEPOSITS THE VAAL RIVER ALLUVIAL GRAVELS...Plate No. 96. THIN SECTION (359, X 12) FONTEIN MINE BRONZITE PERIDOTITE FROM JAGERS facing page 368...following plate MINE THIN SECTION (8, x 12) BRONZITE PERIDOTITE FROM BuLTFONTEIN 98. MINE ,, ,, 99. THIN...THIN SECTION MINE - (3, X 12) BRONZITE PERIDOTITE FROM BOLTFONTEIN 102. THIN SECTION (176, X 12) ENSTATITE |  | | Book | | calcite, clay minerals and fragments of crustal and local host country-rock. At Lattavaram the kimberlite... fine grained matrix of serpentine, calcite, phlogopite and magnetite-rich spinel. Minor monticellite...consists predominantly of serpentine, calcite, minor phlogopite and opaque phases. 94550 I including spinel...Iherzolite nodules in kimberlites(from Lesotho and South Africa) and were analysed for isotopic compositions...Extended Abstract, First Kimberlite Conference, Cape Town, 23. Basu, A. R. and Murthy, V. R.(1977) EPSL |  | | Journal (article/letter/editorial) | | Geology Department, University o f Cape Town, Cape Town (South Africa) and J.J. GURNEY Geochemistry Department...Department, University o f Cape Town, Cape Town (South Africa) Received March 11, 1975 Sharp has proposed...kimberlites involving plate tectonics and has used South Africa as the main example. This hypothesis is open...tendency for it to rebound. (2) The concept of the Cape Fold Belt as representing a subduction zone is probably...incorrect. The belt resulted from the deformation of the Cape Karroo Trough which has a maximum sediment thickness |  | | Journal (article/letter/editorial) | | lherzolite nodules containing K-richterite and/or phlogopite are products of series of metasomatic reactions...garnet lherzolites and two lherzolites containing phlogopite and K-richterite were studied. The sample localities...Monastery Mine, South Africa, and omphacite and garnet from an eclogite from the Roberts Victor Mine, South...South Africa. The samples from Monastery and Roberts Victor were analyzed for the trace elements by J.L...e 2, a sample f r o m the F r a n k Smith pipe, S o u t h Africa ( F R B 81) a n a l y z e d by Boyd |  | | Journal (article/letter/editorial) | | low melting temperatures, such as calcite and phlogopite, present within the thermal aureole surrounding...are common megacryst phases, while subordinate phlogopite and zircon have been recorded at some localities...isotopically distinctive Group I kimberlites recognized by Smith (1983), which broadly correspond to the basaltic...Jagersfontein (Hops et al. 1989, 1992) in southern Africa. (The locations of these and other southern African...clinopyroxene megacrysts, which they termed ‘‘Granny Smith’’ diopsides, from Jagersfontein and a number of |
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