 | | Journal (issue) | | Goldschmidtite -A New Mineral Discovered in a Diamond Henvig Peick.mans henvig.pelckmans@gmail.com Thanks...Nicole Meyer. a Ph.D. student at DERTS (= the Diamond Exploration and Research Training School at the...in a diamond fi-om South Afi-ica. The diamond in question had been found at the Koffiefontein Mine, located...located in the village of Koffiefontein, in the Xhariep District of the Freestate Province. What's not...not to love about the South Afi-ican language? Koffiefontein translates to Coffee Fountain! Who would not |  | | Journal (article/letter/editorial) | | W. HARRIS~ of Geosciences, The Pennsylvania State University, University Park, PA 16802, USA āDepartment...sulfide mineral inclusions among diamond suites from Koffiefontein, Orapa, Premier, Roberts Victor, Jagersfontein...paragenesis. Considering the Ni/Fe ratios of the diamond mss inclusions and mantle olivines, together with...inclusions of the African diamonds (mostly from Koffiefontein) could have been in chemical equilibrium with...relative abundance of silicate inclusions in Koffiefontein diamonds (93% peridotitic, 7% eclogitic) and |  | | Journal (article/letter/editorial) | | diamonds from the Jagersfontein and Koffiefontein kimberlite, South Africa PETER DEINES,āJ. W. HARRIS,ā and...GURNEYS āDepartment of Geosciences, The Pennsylvania State University, University Park, PA 16802, USA 2Department...Department, University of Cape Town, Rondebosch 7700, South Africa (Received September 19, 1990; accepted in revised...diamonds, from the Jagersfontein kimberlite, South Africa, have a 613Crange from - 18.9 to -24.4%0 vs...vs. PDB. Deep diamonds from the nearby Koffiefontein mine have 613Cvalues between -2.9 and -6.1 %o.At these |  | | Journal (article/letter/editorial) | | constraints on cratonic mantle refertilization and diamond formation Christine E. Miller & Maya Kopylova &...with similar datasets available for Ekati and Koffiefontein kimberlites, suggest a general pattern of metasomatic...on the ambient mantle by formation of fibrous diamond. Calcium and Fe enrichment of peridotitic garnet...enrichment of olivine associated with fibrous diamond-forming fluids contributes to refertilization of...and pyroxenes is expected in local mantle segments during fibrous diamond production, as Ca in the carbonatitic |  | Meyer, Nicole A., Wenz, Michelle D., Walsh, James P.S., Jacobsen, Steven D., Locock, Andrew J., Harris, Jeffrey W. (2019) Goldschmidtite, (K,REE,Sr)(Nb,Cr)O3: A new perovskite supergroup mineral found in diamond from Koffiefontein, South Africa. American Mineralogist, 104 (9) 1345-1350 doi:10.2138/am-2019-6937 | Journal (article/letter/editorial) | | perovskite supergroup mineral found in diamond from Koffiefontein, South Africa Nicole A. Meyer1,*, Michelle D...found as an inclusion in a diamond from the Koffiefontein pipe in South Africa. In addition to the dark...dark green and opaque goldschmidtite, the diamond contained a Cr-rich augite (websteritic paragenesis) and...peak at 815 cmā1, which is possibly a result of local ordering of Nb and Cr at the B site. The name goldschmidtite...Perovskite, niobium, mantle, diamond inclusion, new mineral, Koffiefontein, Kaapvaal Introduction Diamonds |  | Naidoo, P., Stiefenhofer, J., Field, M., Dobbe, R. (2004) Recent advances in the geology of Koffiefontein Mine, Free State Province, South Africa. Lithos, 76 (1) 161-182 doi:10.1016/j.lithos.2004.04.032 | Journal (article/letter/editorial) | | advances in the geology of Koffiefontein Mine, $ Free State Province, South Africa P. Naidoo a,b,*, J. Stiefenhofer...Beers Koffiefontein Mine, South Africa De Beers Mineral Resource Management, CHQ, South Africa c De Beers...Beers Geoscience Centre, South Africa d De Beers Central Mines, South Africa e De Beers Mineral Resource...geology of the Koffiefontein pipe has contributed to the marginal nature of the mine. The key to this...work indicates that the kimberlite pipe at Koffiefontein consists of precursor dykes (the West and East |  | | Book | | LEGACY OF THE MINE LEGACY OF THE MINE LEGACY OF THE MINE ILAN GODFREY JACANA CONTENTS The...The Long (and Dark) Shadow of Mining in South Africa 10 The Photographs 7 Extended Captions 131 ...went Noe rani ese talicim'y z i Palabora Copper Mine, Phalaborwa, Limpopo, 2013. = SS > a 7 =i...Ose The Long (and Dark) Shadow of Mining in South Africa Sakhela Buhlungu For nearly 150 years the mining...mining industry has been the catalyst for South Africaās economic development and therefore the countryās |  | | Book | | Diamond Geology Published on www.debeersgroup.com Index A) Classification and genetic models B) Exploration...Sample Treatment D) World Production E) South African Diamond Occurrences 1. Large Kimberlite Mines 1...1.4 Kimberley 1.5 Koffiefontein 2. Smaller mineralised kimberlites in South Africa 2.1 The Oaks 2.2 The...Terms Diamond Geology Page 2 www.debeersgroup.com A) CLASSIFICATION AND GENETIC MODELS Diamond deposits... their relative production contributions in South Africa were, primary (kimberlite) 8.63 million carats |  | | Journal (article/letter/editorial) | | N-Ī“13C-inclusion profiles of cloudy diamonds from Koffiefontein: Evidence for formation by continuous Rayleigh...N-Ī“13Cinclusion profiles of cloudy diamonds from Koffiefontein: Evidence for formation by continuous Rayleigh...N-Ī“13C-inclusion profiles of cloudy diamonds from Koffiefontein: evidence for formation by continuous Rayleigh...zone (ācloudy diamondsā) from the Koffiefontein mine, South Africa, were investigated for N concentrations...evaluates the nature of the change from fibrous to gem diamond growth and the relation between major element |  | | Journal (article/letter/editorial) | | mineral inclusions in cloudy diamonds from Koffiefontein, South Africa ELAD S. IZRAELI,1,* JEFFREY W. HARRIS...in microinclusions in cloudy diamonds from Koffiefontein. The silicates belong to either the eclogitic...the larger mineral inclusions found in other Koffiefontein diamonds and record similar pressures and temperatures...mineral phases that were not detected before in Koffiefontein: phlogopite, high-Si mica, an Al-Mg-rich phase...with the high proportion of cloudy diamonds in Koffiefontein, suggest that brine penetration into neighboring |  | | Report (issue) | | cave going at Finsch Below: This 32 carat pink diamond is a magnificent example of the high quality pink...pink diamonds for which the Williamson mine is known and sold for US$15 million in FY 2016 OUR MISSION...Optimise recoveries Improving operating margins at each mine Drive efficiencies Maintaining a culture of effective...Governance Petra Diamonds is a leading independent diamond mining group and a growing supplier of rough diamonds...benefit of this work as we are in line to become free cashflow positive in H2, with our cashflow profile |  | | Journal (article/letter/editorial) | | com/locate/lithos Mantle fluid evolutionāa tale of one diamond Ofra Klein-BenDavid a,*, Elad S. Izraeli a, Erik...Microinclusions analyzed in a coated diamond from the Diavik mine in Canada comprise peridotitic minerals...range between a carbonatitic melt and brine. The diamond is concentrically zoned. The brine microinclusions...change in the carbon isotopic composition of the diamond from 8.5x in the inner zone to 12.1x in the outer...compositional range found in diamond ON-DVK-294 is the widest ever recorded in a single diamond. It closes the gap |  | Timmerman, Suzette, Honda, Masahiko, Phillips, David, Jaques, Alan L., Harris, Jeffrey W. (2018) Noble gas geochemistry of fluid inclusions in South African diamonds: implications for the origin of diamond-forming fluids. Mineralogy and Petrology, 112. 181-195 doi:10.1007/s00710-018-0603-x | Journal (article/letter/editorial) | | fluid inclusions in South African diamonds: implications for the origin of diamond-forming fluids Suzette...part of Springer Nature 2018 Abstract Fibrous diamond growth zones often contain abundant high-density...and these provide the most direct information on diamond-forming fluids. Noble gases are incompatible elements...the Finsch (n = 3), DeBeers Pool (n = 7), and Koffiefontein (n = 3) mines on the Kaapvaal Craton. C isotope...vary between 268 and 867 at.ppm, except for one diamond with contents of <30 at.ppm N. Nine of the thirteen |  | HANSON, E.K., MOORE, J.M., BORDY, E.M., MARSH, J.S., HOWARTH, G., ROBEY, J.V.A. (2009) CRETACEOUS EROSION IN CENTRAL SOUTH AFRICA: EVIDENCE FROM UPPER-CRUSTAL XENOLITHS IN KIMBERLITE DIATREMES. South African Journal of Geology, 112 (2) 125-140 doi:10.2113/gssajg.112.2.125 | Journal (article/letter/editorial) | | A. ROBEY 125 CRETACEOUS EROSION IN CENTRAL SOUTH AFRICA: EVIDENCE FROM UPPER-CRUSTAL XENOLITHS IN KIMBERLITE...Rhodes University, P.O. Box 94, Grahamstown, South Africa email: emilykhanson@gmail.com; j.moore@ru.ac...Kimberley, South Africa email: jock.robey@debeersgroup.com Ā© 2009 June Geological Society of South Africa ABSTRACT...fourteen Group I kimberlite diatremes in central South Africa were examined for upper crustal xenoliths in...eruption (~85 Ma), they were restricted to the south-eastern half of the study area. At the latter time |  | Aulbach, Sonja, Shirey, Steven B., Stachel, Thomas, Creighton, Steven, Muehlenbachs, Karlis, Harris, Jeff W. (2009) Diamond formation episodes at the southern margin of the Kaapvaal Craton: ReāOs systematics of sulfide inclusions from the Jagersfontein Mine. Contributions to Mineralogy and Petrology, 157 (4) 525-540 doi:10.1007/s00410-008-0350-9 | Journal (article/letter/editorial) | | DOI 10.1007/s00410-008-0350-9 ORIGINAL PAPER Diamond formation episodes at the southern margin of the...systematics of sulfide inclusions from the Jagersfontein Mine Sonja Aulbach Ć Steven B. Shirey Ć Thomas Stachel...Os isotopic composition for both generations of diamond suggests that components with high time-integrated...but significantly lower 187 Os/188Os hosted in a diamond with less aggregated N may represent part of a...during later re-introduction of sulfur. Keywords Diamond Sulfide Inclusion Eclogite Peridotite |  | | Journal (article/letter/editorial) | | in diamonds from the Koffiefontein kimberlite, S Africa: constraints on diamond ages and mantle ReāOs...Department of Geological Sciences, Durham University, South Road, Durham DH1 3LE, UK Department of Terrestrial...(P-type) parageneses in diamonds from the Koffiefontein mine, South Africa have been analysed using a technique...from the same diamond define the first mineral isochron obtained for a single diamond which has an age...indicates that the sulphides, and hence the host diamond, crystallised close to the time of kimberlite emplacement |  | | Journal (article/letter/editorial) | | magnesiowiistite: implications for the origin of inclusions in diamond and the composition of the lower mantle S.E. K...inclusions in diamond provide valuable information about the environment in which the diamond originally...that was heated with an infrared laser beam in a diamond anvil high pressure cell. Run products were characterized...enstatite and magnesiowiistite inclusion assemblage in diamond is entirely consistent with equilibration at lower...substantially lower than those of their counterparts in diamond. However, mass-balance considerations indicate |  | | Journal (article/letter/editorial) | | Accepted Manuscript Diamond-forming media through time ā trace element and noble gas systematics of diamonds...Timmerman, S., Krebs, M.Y., Pearson, D.G., Honda, M., Diamond-forming media through time ā trace element and...apply to the journal pertain. 1 For GCA 2 3 Diamond-forming media through time ā trace element and...peridotite/eclogite paragenesis 15 from Southern Africa (Koffiefontein, Letlhakane, Orapa) were studied for trace...isotopes reside within the same 26 locations in diamond and track the same processes that are reflected |  | | Journal (article/letter/editorial) | | inclusions in diamond, diamond composition, and the lithospheric seismic structure of Southern Africa Steven... Rondebosch 7701, South Africa d Department of Geological Sciences, Arizona State University, Box 871404...Department of Mineral Sciences, The Pennsylvania State University, University Park, PA, USA g De Beers...GeoScience Centre, PO Box 82232, Southdale, 2135, South Africa Abstract The Archean lithospheric mantle beneath...Southern Africa shows F 1% variations in seismic P-wave velocity at depths within the diamond stability |  | | Journal (article/letter/editorial) | | the Precambrian mantle lithosphere of southern Africa Steven B. Shirey Department of Terrestrial Magnetism...Sciences, University of Cape Town Rondebosch 7701, South Africa, e-mail: shr@geology.uct.ac.za Jeffrey W. Harris...Geological Society of South Africa ABSTRACT Two decades of diamond research in southern Africa allow the age...diamonds from the Kimberley area kimberlites, Koffiefontein, Orapa and Jwaneng have Re-Os isotopic ages...the diamond stability field (150 to 225km). Silicate inclusions in diamonds and their host diamond compositions |  | | Journal (article/letter/editorial) | | elsevier.com/locate/lithos Integrated models of diamond formation and craton evolution Steven B. Shirey...Sciences, University of Cape Town, Rondebosch 7701, South Africa c Division of Earth Sciences, University of...online Abstract Two decades of diamond research in southern Africa allow the age, average N content...diamonds from the Kimberley area kimberlites, Koffiefontein, Orapa and Jwaneng have Re ā Os isotopic ages...the diamond stability field (150 ā 225 km). Silicate inclusions in diamonds and their host diamond compositions |  | | Journal (article/letter/editorial) | | 1007/s00710-018-0613-8 ORIGINAL PAPER The involvement of diamond-forming fluids in the metasomatic ācocktailā of...investigate relationships between mantle metasomatism, diamond formation and kimberlite eruptions in intracratonic...the Finsch Group II kimberlite, South Africa, and identified two diamond populations: āFinsch IaAā diamonds...and the neighbouring Group I kimberlites at Koffiefontein and De Beers Pool indicate that a substantial...direct relationship between saline metasomatism, diamond formation and the Kaapvaal late-Mesozoic ākimberlite |  | | Journal (article/letter/editorial) | | inclusions from De Beers Pool diamonds, Kimberley, South Africa D. Phillips a,*, J.W. Harris b, K.S. Viljoen...Mines Ltd., P.O. Box 82232, Southdale, 2135, South Africa b Received 27 June 2003; accepted 14 December...important De Beers Pool kimberlites in Kimberley, South Africa, are characterised by harzburgitic compositions...inclusions record the conditions at the time of diamond crystallisation ( f 1200 jC; f 3.0 Ga). The lower...Phillips et al. / Lithos 77 (2004) 155ā179 between diamond and silicate inclusions. However, thermodynamic |  | | Journal (article/letter/editorial) | | in fibrous and cloudy diamonds ā A glance into diamond dissolution events Ofra Klein-BenDavid a,ā, Richard...internal cavities in diamonds preserve evidence of diamond dissolution events. Combining the methods of focused...carbonates, Al-oxide, fluorite, ilmenite and secondary diamond crystals. The amorphous matrix is spongy and its...introduction of oxidizing hydrous fluids into the diamond growth area. Hydrous fluids are the main dissolving... Canil, D., Semenets, E., 2007. Mechanisms of diamond oxidation and their bearing on the fluid composition |  | | Journal (article/letter/editorial) | | ā 154 www.elsevier.com/locate/lithos Episodic diamond genesis at Jwaneng, Botswana, and implications...Sciences, University of Cape Town, Rondebosch 7701, South Africa Department of Terrestrial Magnetism, Carnegie...characterizing the relationship between episodic diamond genesis and Kaapvaal craton evolution. Kimberley...eastern Kaapvaal. Jwaneng has two main eclogitic diamond generations (2.9 and 1.5 Ga) reflecting both stabilization...Archean vs. Proterozoic diamond formation evident in the Kimberley and Premier diamond suites, respectively |
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