 | | Journal (article/letter/editorial) | | Craton—the peridotitic inclusion suite in diamonds from Orapa and Jwaneng Received: 11 August 2003 / Accepted:...December 2003 Springer-Verlag 2003 Abstract The Orapa and Jwaneng kimberlites are located along the western...affected rocks will be limited. In a few garnets from Orapa preferential MREE enrichment is observed, suggesting...in stark contrast to lithospheric sections for Orapa and Jwaneng based on mantle xenocrysts and xenoliths...subcalcic garnets. Examples are the Premier and De Beers Mine kimberlites in South Africa (Gurney 1984; Griffin |  | Aulbach, S., Jacob, D.E., Cartigny, P., Stern, R.A., Simonetti, S.S., Wörner, G., Viljoen, K.S. (2017) Eclogite xenoliths from Orapa: Ocean crust recycling, mantle metasomatism and carbon cycling at the western Zimbabwe craton margin. Geochimica et Cosmochimica Acta, 213. 574-592 doi:10.1016/j.gca.2017.06.038 | Journal (article/letter/editorial) | | Accepted Manuscript Eclogite xenoliths from Orapa: Ocean crust recycling, mantle metasomatism and carbon...Simonetti, S.S., Viljoen, K.S., Eclogite xenoliths from Orapa: Ocean crust recycling, mantle metasomatism and...the journal pertain. Eclogite xenoliths from Orapa: Ocean crust recycling, mantle metasomatism and...xenoliths from Orapa, at the western margin of the Zimbabwe craton (central Botswana), were investigated...phlogopite-rich metasome. The overlap of diamondiferous and graphite-bearing eclogites and pyroxenites over a pressure |  | | Journal (article/letter/editorial) | | inclusion chemistry beneath the Orapa kimberlite cluster, in Botswana Peter Deines a,1, Thomas Stachel...online 5 April 2009 Keywords: Diamond Damtshaa Orapa Letlhakane Carbon isotope Regional variation a b s t...compared with similar studies of the nearby Orapa and Letlhakane kimberlites, providing the opportunity to...composition on the kilometer scale. While Orapa, Letlhakane and Damtshaa diamonds may share some overall...of km. Compared to Orapa, peridotitic garnet inclusions from Damtshaa and Letlhakane are derived, in part |  | | Journal (article/letter/editorial) | | two closely associated kimberlites: Letlhakane and Orapa, Botswana P. Deines a,*, J.W. Harris b a Department...Carbon isotope measurements on diamonds from the Letlhakane kimberlite, and the analyses of their inclusions...results with those for the nearby Orapa kimberlite. Diamonds from Letlhakane have a wide range in carbon isotopic...depleted in 13C is significantly lower than in the Orapa kimberlite. Most of the 13C-depleted diamonds belong...two locations. At Letlhakane, peridotitic compositions are more prevalent than at Orapa and the protolith |  | | Journal (article/letter/editorial) | | the discovery of diamonds in river deposits in central South Africa in the mid nineteenth century, it...valuable deposits were discovered in South Africa and Botswana in particular, but also in Lesotho, Swaziland...Jwaneng in Botswana, to mines that are both small and marginal, such as the Frank Smith Mine in South Africa...Africa. They include large diatremes such as Orapa and small dykes such as those mined at Bellsbank,...terrane; IIb: Central terrane; IIc: Pietersburg terrane; IId: Western terrane; IIIa: Central zone; IIIb: |  | | Journal (article/letter/editorial) | | geochemistry of peridotite xenoliths from the Letlhakane kimberlites, Botswana Received: 19 March 1996 / Accepted:...diamondiferous Letlhakane kimberlites are intruded into the Proterozoic Magondi Belt of Botswana. Given the...mantle under eastern Botswana we have studied peridotite xenoliths from the Letlhakane kimberlites. The mantle-derived...mantle-derived xenolith suite at Letlhakane includes peridotites, pyroxenites, eclogites, megacrysts...peridotites from the Kaapvaal craton is not seen in the Letlhakane xenoliths. The P-T data indicate the presence |  | | Journal (article/letter/editorial) | | of Springer Nature 2018 Abstract Bechuanaland/Botswana has a long and colourful history in exploration...pre-historic, historic and modern. Quarrying stone in Botswana was ongoing 500,000 years ago during the Early...Late Stone Age (LSA) 20,000 to 2,000 BP. In east Botswana iron and copper were mined from AD 800 onwards;...to the discovery of the Orapa kimberlite field in 1967, a year after Botswana became independent. This...boom across Botswana adding important diamond-bearing kimberlites such as at Letlhakane (1968), Jwaneng |  | | Journal (article/letter/editorial) | | silicate inclusions from the Orapa and Letlhakane diamond mines, Botswana. δ 13 C values are reported...change in the nature of subducted carbon beneath Botswana and warrant further study to establish if this...Southern Africa showing the location of the Orapa and Letlhakane diamond mines on the edge of the Zimbabwe...and cathodoluminescence images of Orapa diamond 02 and Letlhakane diamond 09 respectively. Diamond OR02...inclusions from 16 diamonds from the Orapa and Letlhakane diamond mines, Botswana. Each diamond was first characterised |  | | Journal (article/letter/editorial) | | Unusually Fe- and Ni-rich macrocrysts unique to the Lace mine are from Fe-rich orthopyroxene-bearing peridotites...has chemical characteristics similar to Orapa and Letlhakane suites, which suggests closer affinity to...inhabituels riches en Fe et en Ni provenant de la mine Lace semblent uniques; ils se sont formés à partir...caratéristiques avec celui des suites d’Orapa et de Letlhakane, ce qui pourrait indiquer une affinité plus grande...Archean cratonic units in southern Africa. 1 Orapa, 2 Letlhakane, 3 Jwaneng, 4 Finsch, 5 Bobbejaan, 6 Frank |  | | Journal (article/letter/editorial) | | Hyderabad, and the only modern producing diamond mine in India exploits the Majhgawan lamproite pipe near...about 1920 Zaire (now the Congo Republic), Angola, Botswana, Russia and Australia, in that chronological order...collector markets (Sullivan, 1978; Moore, 1995). The mine at Mir is now idle and flooded, but Udachnaya continues...under Lac de Gras, in the Arctic wilderness of the central Northwest Territories: see Kevin Krajick’s recent...events leading to the opening of the Ekati diamond mine there, in 1998. Presently Venezuela, Guyana, Indonesia |  | | Journal (article/letter/editorial) | | Moore African Queen Mines Limited, Box 66 Maun, Botswana. Department of Geology, Rhodes University, Grahamstown...of rare Orapa diamonds with websterite inclusions, arguing for a common paragenesis. The Orapa websterite...kimberlites, and overlap the compositional field for Orapa garnet megacrysts. These chemical characteristics...found, the 3106 Cullinan, recovered from the Premier Mine, South Africa (Williams, 1932), as well as gems...kindly provided by Debbie Bowen of Letseng Diamond Mine, illustrates a selection of Type IIa stones from |  | | Journal (article/letter/editorial) | | evaluation geophysics was first used successfully in Botswana (de Wit 2018): the contrasting petrophysical INTRODUCTION...user D ecember 2019 Kimberlite geology is the central thread running through diamond exploration, and...Cretaceous Orapa kimberlite in Botswana was discovered by recognizing a significant post–Orapa age crustal...the intersection of the paleogeotherm with the graphite–diamond transition curve, and with the A A Regional...et al. 2008). E lements 50 100 Cr-pyrope in graphite stability “Diamond Window” Significant advances |  | | Journal (article/letter/editorial) | | diamond from the Damtshaa mine, which comprises four kimberlites within the Orapa cluster of kimberlites...cratonic eclogite xenoliths worldwide, at the nearby Orapa Mine, and of oceanic crust. Contrary to previous suggestions...garnet inclusions in diamond from the Damtshaa mine, Botswana, to show that there is a clear relationship...kimberlites are part of the Orapa cluster of Group 1 kimberlites in central Botswana (Field et al., 2008)....west of the main Orapa kimberlite. Diamonds and xenoliths from the mine at the Orapa kimberlite have been |  | | Journal (article/letter/editorial) | | lithospheric mantle is cooler (see text) causing the graphite/diamond transition to occur at lower pressure...inclusion-bearing diamonds from the mines of South Africa and Botswana was begun by Gurney and Harris (multiple papers...mantle. As a consequence of lower temperatures the graphite-diamond transition is raised to shallower depth...diamonds is not known. In early work (1973–1985) run-of-mine diamonds in the sieve class −6 + 5 (1.83 mm aperture...+ 5 sieve class) in run-of-mine productions from South Africa and Botswana are listed in Table 1 and range |  | | Journal (article/letter/editorial) | | mantle below Swaziland to that below southeastern Botswana, roughly following the surface outcrop pattern...the Kimberley area kimberlites, Koffiefontein, Orapa, and Jwaneng have Re – Os isotopic ages that range...Jagersfontein, Roberts Victor, Premier, Venetia, and Letlhakane do show some regional relationship to the seismic...literature and the ongoing work of Shirey et al. (Orapa) and Richardson et al. (Jwaneng). It is important...separate diamonds) occur commonly (e.g. Jwaneng, Orapa, and Premier). An ideal situation would be to have |  | | Journal (article/letter/editorial) | | 414 — 423 ( Springer-Verlag 1995 K.S. Viljoen Graphite- and diamond-bearing eclogite xenoliths from the...Bellsbank kimberlites, Cape Province, South Africa. Graphite mostly occurs as discrete grains which are commonly...Group II eclogite varieties are represented by the graphite-bearing specimens, while the single diamond-bearing...variety. The carbon isotopic composition of the graphite varies from d13C"!7& to d13C"!2.8&. This is within...isotopic compositions of clinopyroxene from three graphite-bearing xenoliths are slightly higher than the |  | | Journal (article/letter/editorial) | | the Kimberley area kimberlites, Koffiefontein, Orapa and Jwaneng have Re-Os isotopic ages that range...Jagersfontein, Roberts Victor, Premier, Venetia and Letlhakane show a regional relationship to the seismic velocity...eclogitic (Jagersfontein=JA, Jwaneng=JW, Letlhakane=LE, Orapa=O, Premier =P) and green squares are localities...southern African diamonds. Kimberlite Jwaneng Letlhakane Orapa Premier Venetia De Beers Pool Finsch Roberts...Koffiefontein (Deines et al., 1991a; Pearson et al., 1998); Orapa (Richardson et al., 1990, Shirey, unpublished data; |  | | Journal (article/letter/editorial) | | the Kimberley area kimberlites, Koffiefontein, Orapa and Jwaneng have Re – Os isotopic ages that range...Jagersfontein, Roberts Victor, Premier, Venetia, and Letlhakane show a regional relationship to the seismic velocity...averaged. This cylinder is centered below each diamond mine and extends from 150 to 225 km depth. Seismic data...southern African diamonds Kimberlite Jwaneng Letlhakane Orapa Premier Venetia De Beers Pool Finsch Roberts...Koffiefontein (Deines et al., 1991a; Pearson et al., 1998); Orapa (Richardson et al., 1990; Deines et al., 1991b, |  | | Report (issue) | | -i- REPUBLIC OF BOTSWANA MINERAL RESOURCES REPORT NO. 3 RESOURCES _JNVENTORY INDUSTRIAL·· ROCKS...ROCKS N. OF BOTSWANA: AND MINERALS w. D. MASSEY, B. SC. PRICE TWO RAND PUBLISHED BY GEOLOGICAL PRINTED...DEPARTMENT, PRINTER, LOBAT GABORONE, BoT E, BOTSWANA WANA MINERAL RESOURCES REPORT NO. 3 RESOURCES...RESOURCES INVENTORY INDUSTRIAL ROCKS N. w. D. OF BOTSWANA: AND MINERALS MASSEY, B. SC. CONTENTS Abstract...Introduction 2. A brief outline of the geology of Botswana 3. Asbestos 4. Barytes 5. Clays: 5. l Brickearths |  | Mikhail, S., McCubbin, F. M., Jenner, F. E., Shirey, S. B., Rumble, D., Bowden, R. (2019) Diamondites: evidence for a distinct tectono-thermal diamond-forming event beneath the Kaapvaal craton. Contributions to Mineralogy and Petrology, 174 (8) doi:10.1007/s00410-019-1608-0 | Journal (article/letter/editorial) | | gem monocrystalline diamond-formation events at Orapa. The modelled fluid compositions responsible for...source(s) for the diamondite-forming fluids at Orapa, Botswana. These data are used to contrast diamondite-formation...come from the main Orapa kimberlite, Botswana, the largest of 23 pipes in the Orapa cluster in north-eastern...north-eastern Botswana, 250 km west of Francistown. The Orapa kimberlite was emplaced 93.1 Ma (Davis 1977)...polycrystalline diamond. The mining process at Orapa involves jaw-crushing the kimberlite, so these samples |  | | Journal (article/letter/editorial) | | but are particularly common in diamonds from the Central- and WestAfrican cratons (Fig. 2). For the lherzolitic...clearly present in diamonds from the Kalahari, the Central- and the West-African cratons, but so far, has...Gurney et al. (1984) in a study of diamonds from the Orapa kimberlite and may be loosely defined as being intermediate...Venetia, De Beers Pool, and Namibia whereas at Orapa, Letlhakane, and Jagersfontein websteritic diamonds are...δ13C, Mg-number and Ni content) and the West and Central African cratons (elevated δ13C and high Mg-number |  | Howell, D., Stachel, T., Stern, R.A., Pearson, D.G., Nestola, F., Hardman, M.F., Harris, J.W., Jaques, A.L., Shirey, S.B., Cartigny, P., Smit, K.V., Aulbach, S., Brenker, F.E., Jacob, D.E., Thomassot, E., Walter, M.J., Navon, O. (2020) Deep carbon through time: Earth’s diamond record and its implications for carbon cycling and fluid speciation in the mantle. Geochimica et Cosmochimica Acta, 275. 99-122 doi:10.1016/j.gca.2020.02.011 | Journal (article/letter/editorial) | | Dutoitspan, and Wesselton kimberlites), Jwaneng and Orapa, ages were obtained by Re-Os analysis of individual...1), De Beers Pool (n = 1), Jwaneng (n = 4) and Orapa (n = 1) also reveal some portions of cuboid growth...growth events (4 out of 10 samples), while the Orapa (11 out of 13 samples) and Jwaneng (11 out of 16...1990), so carbon isotope data for diamonds from this mine of known paragenesis (e.g. Appleyard et al., 2004;...Attawapiskat (Ontario) kimberlites of the eastern and central Superior Craton, respectively, show a temporal |  | | Journal (article/letter/editorial) | | Republic of Congo, and the Jwaneng and Orapa kimberlites in Botswana. Initial fusion analyses of clinopyroxene...Step-heating analyses of clinopyroxene inclusions from Orapa and Jwaneng diamonds produced older apparent ages...temperature steps and the ‘rim’ fragment of one Orapa inclusion. High temperature (fusion) analyses yielded...syngenetic inclusions in diamonds from the Mbuji-Mayi, Orapa, Jwaneng and Premier kimberlites. LOCALITY KIMBERLITE...Rb-Sr 71 69.8 ⫾ 0.5 235 ⫾ 4 250 ⫾ 17 1 2 3 3 Orapa Zircon U-Pb 93 1 Premier Phlog WR WR Gnt ⫹ |  | | Journal (article/letter/editorial) | | study of eclogite xenoliths from the Orapa kimberlite, Botswana K.S. Viljoen a,*, Craig B. Smith a, Z...February 1996 Abstract Eclogite xenoliths from Orapa can be accurately classified as Group I or Group...diamond-free. Both xenolith varieties may contain graphite. Isotopic character is to some degree correlated...Sr, Sm, Nd and Pb concentrations of minerals in Orapa Group I eclogite xenoliths are much lower than in...covariation of O and Sr isotopic compositions the entire Orapa Group I eclogite xenolith suite can be modelled |  | Deines, Peter, Harris, J.W., Robinson, D.N., Gurney, J.J., Shee, S.R. (1991) Carbon and oxygen isotope variations in diamond and graphite eclogites from Orapa, Botswana, and the nitrogen content of their diamonds. Geochimica et Cosmochimica Acta, 55 (2) 515-524 doi:10.1016/0016-7037(91)90009-t | Journal (article/letter/editorial) | | isotope variations in diamond and graphite eclogites from Orapa, Botswana, and the nitrogen content of their...Abstract-In eclogite xenoliths from Orapa, Botswana, 613Cof graphite varies between -4.6 and -7.8%~ vs...that of diamonds ranges from -4.0 to -22.3%0. In graphite eclogites, 6’*0 values of garnets fall between...36 -t 0.15, n = 6), graphite/diamond eclogites (0.46 rt 0.36, n = 3), and graphite eclogites (0.53 f 0...kimberlite as a whole. In graphite/diamond eclogites from this mine, graphite and diamond are found to |
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