 | | Journal (article/letter/editorial) | | Studsvik Kimberlitic zircons from 16 intrusions in Lesotho, the Republic of South Africa, and Tanzania have...gram per ton or less (Dyke 170, cf. KRESTEN 1972; Kao (0.01 g/t), T. K. WHITELOCK, pets. comm.; Letseng...Dutoitspan in his collection. At Letseng la terae (Lesotho), two small euhedral zircons have been discovered...distinct colours. This is true for diamonds as well. Lesotho kimberlitie zircons are usually colourless, except...that are found in the kimberlites of northern Lesotho also show some fractures and cracks (NlxoN and |  | | Journal (article/letter/editorial) | | (masl) in the rugged Maluti Mountain terrain of Lesotho. The cluster’s intrusion was structurally controlled...Pipes. Keywords Liqhobong . Maluti mountain . Lesotho . Kimberlite . Volcaniclastic . Kimberley-type...(KPK) Introduction Regional geological setting Lesotho is entirely surrounded by South Africa covering...Pension House, Constitutional Rd, Maseru West, Lesotho 2 MPH Consulting Limited, 133 Richmond Street...rocks of the Stormberg Group covers a third of Lesotho and are located mainly on the western margin of |  | | Book | | . . . . . . . . . . . . . . . 6.3.5. Ilmenite-Spinel Intergrowths (Parageneses 5 and 6) ..............of Kimberlite Phlogopites .................... Spinel ................................................................. 6.7. 1. Macrocrystal Spinel (Paragenesis 1) .............................. 6.7. 2. Primary............. 6.7. 5. Macrocrystal And Groundmass Spinel Compositions ................. 6.7. 6. Macrocrystal............................ 6. 7 .10. Kimberlite Spinel Compositional Trends Compared to Those of Other |  | | Journal (article/letter/editorial) | | 361-376 (2001) ORIGINS OF CHROMIAN AND ALUMINOUS SPINEL MACROCRYSTS FROM KIMBERLITES IN SOUTHERN AFRICA...of the major- and minor-element compositions of spinel-group minerals that occur as single-crystal macrocrysts...leads to the conclusion that most macrocrysts of spinel-group minerals are likely to be xenocrysts from...phenocrysts related to the host kimberlites. Chromian spinel with Cr/(Cr + Al) > 0.88 is derived from garnet-free...kimberlites. Moderate degrees of metasomatism produced spinel-group minerals enriched in Fe, Ti and Cr in many |  | | Journal (article/letter/editorial) | | garnets during subsolidus recrystallization of spinel wehrlitic cumulates, which themselves had been...dichroic green-violet varieties from the Kao pipe in Lesotho [2]. This paper establishes the Newlands...[1 ]. Comparisons of the Newlands, Yakutian and Kao green garnets are given in Fig. 1A, B and show that:...different from the xenocrysts of Zagadochnaya and Kao; (b) the green garnet from the Sytikanskaya wehflite...and Ca; (c) the knorringitic green garnets from Kao form a compact grouping distinctly different from |  | | Journal (article/letter/editorial) | | 129-34 Cr-rich spinel and garnet in two peridotite xenoliths from the Frank Smith mine South Africa: Significance...Significance of A1 and Cr distribution between spinel and garnet R. A. EXLEY, J. V. SMITH, AND R. L....garnet (core TiO2 0.8, Cr203 7; rim 1.4, 4 wt. ~o), spinel (TiO 2 5, Cr203 38), clinopyroxene(A1203 1 8) secondary...orthopyroxene (En 93.6), garnet (Cr203 3.1-3.8), spinel (55), ureyitic diopside, primary mica (TiO2 0.06...In 73-106, the spinel lies in secondary mica next to the garnet rim, whereas the spinel of 73-109 occurs |  | | Journal (article/letter/editorial) | | palaeogeotherm in the upper mantle beneath northern Lesotho was inflected in late Cretaceous times, but the...mantle beneath stable cratonic areas, including Lesotho, Premier, Frank Smith, Siberia. Non-inflected geotherms...and temperatures of ultramafic xenoliths in the Lesotho kimberlites from Matsoku (Bishop et aI., 1978;... Liqhobong (Nixon and Boyd, 1973b; Mori, 1975), Kao (Nixon and Boyd 1973c; MacGregor, 1979), Pipe 200...relationships in the upper mantle beneath northern Lesotho at late Cretaceous times (G.L. Davis et al., 1976) |  | | Report (issue) | | = 11.65 Z=8 X-ray Powder Pattern: Kao kimberlite pipe, Lesotho. 2.92 (100), 2.61 (100), 2.382 (80)...Total 100.68 100.00 33.54 26.68 (1) Kao kimberlite pipe, Lesotho; by electron microprobe, corresponding...Polymorphism & Series: Mineral Group: Occurrence: Lesotho). Forms a series with pyrope. Garnet group. ...rare component of ultrama¯c kimberlite nodules (Kao kimberlite pipe, Association: Olivine, enstatite...chromian spinel, ilmenite, perovskite, zircon, diamond, omphacite, rutile, carbonates, micas (Kao kimberlite |  | | Book | | mica-bearing peridotite that in some parts of the mine contained so many xenoliths of carbonaceous shale...(1979) has shown, mainly on the basis of groundmass spinel composition, that some, such as those at Alno (Sweden)...Iramba plateau west of Singida; only the Mwadui Mine at Shinyanga and one near Kahama have been sufficiently...Republic of South Africa, South-West Africa and Lesotho. The inland plateau of South Africa is the region...are more recent accounts of the kimberlites of Lesotho (Nixon 1973b); the kimberlites of S.W. Africa (Janse |  | | Journal (article/letter/editorial) | | occurrence and the fact that shallower-derived spinel-bearing varieties are found in many ultrabasic-basic...use only. Bellsbank • • .. \ • I , , N. Lesotho group Single or rew kimberlites Cluster of kimberlitee...ultradepleted nod ules have been described from northern Lesotho (Carswell et a11979) but they are much more common...constituents. They are well documented from northern Lesotho (Nixon & Boyd 1973b), Jagersfontein (MacGregor...late-stage hydra tion. Coarse,primary chromium-bearing spinel is present in some nodules. Phlogqp!te may- be |  | | Journal (article/letter/editorial) | | ilmenites from kimbedites in South Africa and Lesotho ROGER H. MITCHELL LITHOS Mitchell, R. H. 1977:...ilmenites from kimbcrlites in South Africa and Lesotho. Lia..u~ I"3, 29--37. Oslo. ISSN 00244937. Magnesium...and lamellar intergrowths with pyroxene from the Kao, SekameTag, Frank Smith, and Monastery kimberlites...Table I. Composition of discrete ilmenites from the Kao, Frank Sm,th and Sekameng and lamellar ilmenites...(Monastery, Frank Smith; South Africa; Kao, Sekameng; Lesotho) from South African kimberlites. Major |  | | Journal (article/letter/editorial) | | lherzolite xenoliths in the kimberlites of northern Lesotho: revised P - T equilibration conditions and upper...that the inflected palaeogeotherm for northern Lesotho, previously highlighted by Boyd (1973), Boyd and...reality of an inflected palaeogeotherm for northern Lesotho. Rather, it reflects, at least in part, chemical...estimates for xenoliths in the kimberlites of northern Lesotho indicate a somewhat elevated, non-inflected, upper...the heat flux within the mantle beneath northern Lesotho at the time of emplacement of the Thaba Putsoa |  | Hetman, Casey M., Scott Smith, Barbara, Robey, Jock, Nkotsi, Teboho, Mohapi, Mohapi, Mohapi, Thabang (2018) Letšeng diamond mine, Lesotho: a variant of Kimberley-type pyroclastic kimberlite emplacement. Mineralogy and Petrology, 112. 365-382 doi:10.1007/s00710-018-0642-3 | Journal (article/letter/editorial) | | 1007/s00710-018-0642-3 ORIGINAL PAPER Letšeng diamond mine, Lesotho: a variant of Kimberley-type pyroclastic kimberlite...Springer Nature 2018 Abstract The Letšeng Diamond Mine comprises two ~91 Ma kimberlite pipes. An update...Hypabyssal Introduction The Letšeng Diamond Mine in Lesotho (Fig. 1a) differs from many other mines in...Diamonds (Pty) Ltd., PO Box 12508, Maseru 100, Lesotho in the world. The low grade and low frequency...ongoing diamond resource development upon which mine planning is based. An update of the geology is presented |  | | Journal (article/letter/editorial) | | 1980 Oxide mineralsin the Liqhobongkimberlite, Lesotho Nenn Z. BocToR AND F. R. Boyo Geophy sical Lab...Liqhobong, Lesotho,are representedby discreteilmenite nodules, groundmassilmenite, spinel solid solutions...microprobe. For data reduction of ilmenite and spinel analyses,the correction schemesof Bence and Albee...Each nodule is surrounded by reaction mantles of spinel, secondary ilmenite, and perovskite. These reaction...Liqhobong pipe are plotted in the spinel prism (Fig. 4), the two varietiesof spinel plot as two separate populations |  | | Book (volume) | | the development of analogous plied to eclogites, spinel peridotites and harzburgiteso abundant as xenoliths...Diamond-Graphite Ecologite From the Roberts Victor Mine, C. J. Hatton and John J. Gurney ................. Lower-Crustal Granulites and Eclogites From Lesotho, Southern Africa, W. L. Griffin, D. A. Carswell...and Garnet Harzburgite XenolithsFrom the Premier Mine, South Africa, R. V. Danchin ....................Geochemistryof Ultramarie NodulesFrom Pipe 200, Northern Lesotho, D. A. Carswell, D. B. Clarke, and R. H. Mitchell |  | | Journal (article/letter/editorial) | | h o s Tuffisitic kimberlites from the Wesselton Mine, South Africa: Mineralogical characteristics relevant...Chlorite Diopside Spinel a b s t r a c t Tuffisitic kimberlites from the Wesselton Mine consist, in order...microcrystalline groundmass of diopside, apatite, perovskite, spinel and chloritized and fresh phlogopite, the latter...character of these rocks. We have chosen the Wesselton Mine (South Africa) as the “type locality” for “tuffisitic...or 1.71 km (Hanson et al., 2006). At the Premier Mine, tuffisitic kimberlite occurs over a vertical distance |  | Pearson, D. G., Boyd, F. R., Haggerty, S. E., Pasteris, J. D., Field, S. W., Nixon, P. H., Pokhilenko, N. P. (1994) The characterisation and origin of graphite in cratonic lithospheric mantle: a petrological carbon isotope and Raman spectroscopic study. Contributions to Mineralogy and Petrology, 115 (4) 449-466 doi:10.1007/bf00320978 | Journal (article/letter/editorial) | | craton (Kilnberley, Jagersfontein and northern Lesotho), the Premier pipe in the central part of the Kaapvaal...variable dcpletion in Ca, garnet-spinel lherzolites, garnet thcrzolites, a spinel-facies peridotite and three...of over 200 peridotite xenoliths from the Premier mine, South Africa, yielded 5 graphite-bearing specimens... Olivine Enstatite Garnet Spinel Olivine Estatite Garnet Spinel -52.1 < 0.03 41.4 . < 0.03 <...Enstatite Garnet Olivine Enstatite Garnet Spinel Na20 MgO AlzO3 Sit2 K20 Cat Tit2 Cr203 MnO FeO |  | | Journal (article/letter/editorial) | | eclogite inclusions in kimberlite of Roberts-Victor mine near Kimberley, South Africa, three are essentially...inclusions from kimberlite of the Roberts-Victor mine have been chemically analyzed. Six pairs of coexisting...composition of 18 eclogitesfrom the Roberts-Victor mine given by Willliams (1932, p. 337) is also shown...average of 18 eclogites from the Roberts-Victor Mine (Wiliiams, 1932). relatively mafic-rich region...analyzed eclogites in kimberlite of the Roberts-Victor mine (numbers as in Table 1). Open circles are kyanitefree |  | | Journal (article/letter/editorial) | | Boyd (1973) constructed a 'paleogeotherm', the Lesotho geotherm, from the P—T estimates obtained for suites...obtained by these methods are compared with the Lesotho geotherm of Boyd (1973) (curve a) and the new geotherm...two-pyroxene thermometry (Wells, 1977). Curve a^—Lesotho geotherm of Boyd (1973); Curve b—geotherm of Carswell...equilibration pressures at 20-24 kb at 1100°C for a spinel-garnet lherzolite from New South Wales (Ferguson...1977) are consistent with the presence of both spinel and garnet, and are in good agreement with recent |  | | Journal (article/letter/editorial) | | electron probe confirms that a garnet from Kao kimberlite pipe in Lesotho contains a large proportion of the...has been discredited (:uvarovite). The garnet from Kao, with 17.4TaCrsos, is green, o: 11.65,n:1.803, G...characterisethe ultrabasic nodules of these bodies, chrome-spinel peridotites, their higher level equivalents being...pyrope from E9 lherzolite nodule from Liqhobong, Lesotho, gave 5.14 percent CrzOr and a full analysis of...pyrope from E10 serpentinisednodule from Sekameng,Lesotho gave 7.52 percent Cr2Os(table 1) (Nixon et aI. |  | | Journal (article/letter/editorial) | | matrix of olivine (Foss-92), picroilmenite, Cr-spinel, magnetite, perovskite, pyrrhotite, calcite, and...and 47-49 kb. Spinel peridotites have discordant temperatures of 720 ~ 835~ (using spinel-olivine Fe/Mg)...grains of olivine, picroilmenite, phlogopite, Cr-spinel, perovskite, magnetite (0.1 0.5 ram) in a fine-grained...Cpx + Sp + Ilm+ Mt O1 O1 + Gar spinel lherzolite spinel lherzolite spinel lherzolite garnet lherzolite...lherzolite garnet lherzolite harzburgite spinel websterite mosaic dunite mosaic dunite (A) (A) (A) (B) (B) (C) |  | Wu, Fu-Yuan, Yang, Yue-Heng, Mitchell, Roger H., Li, Qiu-Li, Yang, Jin-Hui, Zhang, Yan-Bin (2010) In situ U–Pb age determination and Nd isotopic analysis of perovskites from kimberlites in southern Africa and Somerset Island, Canada. Lithos, 115 (1) 205-222 doi:10.1016/j.lithos.2009.12.010 | Journal (article/letter/editorial) | | Samples from the Kimberley area include: Wesselton Mine root zone hypabyssal rocks from kimberlite phases...phases W3 and W2 collected at the 680 m level of the mine (W3-680, W2-680a, W2-680b and W2-680c); and an opaque-oxide...South Africa. Samples from Thaba Putsoa (TP7) and Kao (Kao-K1, phase K1 or Gritty kimberlite of Clement (1973))...hypabyssal transitional kimberlites, respectively, from Lesotho. The perovskites in these samples are typically...primitive kimberlite magmas (Mitchell, 2004). The Kao K1 and Thaba Putsoa kimberlites contain fewer perovskite |  | | Journal (article/letter/editorial) | | xenoliths from the kimberlite pipes in Northern Lesotho at the southern margin of the Archean Kaapvaal...pipes to construct a single geotherm for Northern Lesotho, which is a good start toward establishing the...Northern Lesotho kimberlite pipes: 1) Tava Putsoa; 2) Letseng la Terae; 3) Matsoku, Pipe 200, Kao, Motae...Northern Lesotho; 5) Clark-Ringwood shield geo therm (41 mW/m2); 6) Late Cretaceous Northern Lesotho geotherm...seven pipes in Northern Lesotho: Taba Putsoa, Letseng la Terae, Matsoku, Pipe 200, Kao, Motae, and Liqhobong |  | | Book | | serpentine, calcite, phlogopite and magnetite-rich spinel. Minor monticellite and pectolite were also noted...phlogopite and opaque phases. 94550 I including spinel and ilmenite. Minor phases such as sphene and perovskite...32.46 0.29 0.06 0.05 0.02 - - - Table 2. Spinel Spinel Monti- PectoSerpenOJ(2) cellite lite_tine -...to a three-phase mixture of modified spinel(3 phase) or spinel(y phase), stishovite and garnet solid...garnet Iherzolite nodules in kimberlites(from Lesotho and South Africa) and were analysed for isotopic |  | | Journal (article/letter/editorial) | | related to the pressure of crystallization. In the spinel- and garnet-lherzolite fields, above 8 or 10 kbar...basis of six oxygen atoms, Squares = spinel-lherzolites and spinel-harzburgites; stars = plagioclase-bearing...references 19,24,72,73. phases. On the other hand spinel, and to a lesser extent garnet, but not plagioclase...in the plagioclase-lherzolite field than in the spinel- and garnetlherzolite fields. These assumptions...shows [17-191 the transition in the field from the spinel- to the plagioclase-lherzolite facies through the |
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