| | 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 | | | 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...Series: Mineral Group: Occurrence: Lesotho). Forms a series with pyrope. Garnet group. A rare component...nodules (Kao kimberlite pipe, Association: Olivine, enstatite, chromian diopside, chromian pyrope, chromian...carbonates, micas (Kao kimberlite pipe, Lesotho). Distribution: In the Kao kimberlite pipe, Lesotho. From the | | | Book | ............... 6.2.4. Cr-Poor Megacryst Suite Pyrope ................................... 6.2.5. Trace...hamlet of Colesbergthe Kimberley Mine (De Beer's New Rush), the De Beers Mine (De Beer's Old Rush), and the...spell and pronounce the name of the main electoral district by calling it after his Lordship. The names "New...kimberlite provinces were discovered in Tanzania, Lesotho, Colorado-Wyoming (U.S.A.), and Yakutia (U.S.S...ground with descriptions of kimberlite fields in Lesotho and Namibia which were unknown to Wagner and Williams | | | Book | mica-bearing peridotite that in some parts of the mine contained so many xenoliths of carbonaceous shale...talc schists; although diamondiferous, they lack pyrope and ilmenite but contain abundant chromite. In...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) | dichroic green-violet varieties from the Kao pipe in Lesotho [2]. This paper establishes the Newlands...the Newlands green garnets are largely uvarovite-pyrope-grossular solid solutions, these experimental results...[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) | 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...and their significance discussed. INrnoouctrorq Pyrope garnets containing chromium have long been known...partial analysis of chromium pyrope from E9 lherzolite nodule from Liqhobong, Lesotho, gave 5.14 percent CrzOr...analysis of chromium pyrope from E10 serpentinisednodule from Sekameng,Lesotho gave 7.52 percent Cr2Os(table | | | Journal (article/letter/editorial) | eclogite inclusions in kimberlite of Roberts-Victor mine near Kimberley, South Africa, three are essentially...contain kimberlitic minerals such as ilmenite and pyrope-rich garnet. Thus, it seems probable that in kimberlites...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 | | | Journal (article/letter/editorial) | Unusually Fe- and Ni-rich macrocrysts unique to the Lace mine are from Fe-rich orthopyroxene-bearing peridotites...inhabituels riches en Fe et en Ni provenant de la mine Lace semblent uniques; ils se sont formĂ©s Ă partir...Star, 11 Lace, 12 Jagersfontein, 13 Liqhobong and Kao, 14 Monastery. Craton boundaries after de Wit et...Frank Smith, Monastery in South Africa, Kao and Liqhobong in Lesotho, and Jwaneng, Letlhakane and Orapa in...(primarily 0.5â1.0 mm), with a few from the Lace mine in the range 3.0â4.0 mm. In addition, approximately | | | Journal (article/letter/editorial) | Boyd (1973) constructed a 'paleogeotherm', the Lesotho geotherm, from the PâT 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^âLesotho geotherm of Boyd (1973); Curve bâgeotherm of Carswell...estimates which lie between the lower limbs of the Lesotho geotherms derived by Boyd (1973) and by Carswell...clinopyroxene for compositions of the diopside-pyrope join in the system CaSiOj-MgSiOj-AljOj. Yb. Carnegie | | | Journal (article/letter/editorial) | nodules. The kimberiite minerals include ilmenite, pyrope, diopside (with probably omphacitic varieties)...ultrabasic nodules consist essentially of chrome pyrope. chrome diooside. enstatite and forsteritic olivine...eclogite-granulite-amphibolite nodule group is characterised by pyrope-almandine, omphacitic clinopyroxene, rutile, and...larger intrusions, for example, the I mile diameter Kao pipe. PBrnocnapnv Kimberliles. The three well known...limonitic secondary mineral aggregate. Ilmenite, pyrope and chrome diopsidemay be conspicuousin this highly | | | Book (volume) | 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...... 145 Mafic and Ultramafic Xenoliths From the Kao Kimberlite Pipe, Ian D. MacGregor .............. | | | Journal (article/letter/editorial) | in two peridotite xenoliths from the Frank Smith mine South Africa: Significance of A1 and Cr distribution... (1979) and Mitchell et al. (1980), Pipe 100, Lesotho; Danchin (1979), Premier, S. Africa; Ferguson et...MacGregor (1979), Kao, Lesotho; Nixon and Boyd (1973), Thaba Putsoa and Mothae, Lesotho; Smith and Dawson...in two peridotite xenoliths from the Frank Smith mine, Bellsbank, S. Africa. Associated micas are significant...ratios are similar. The garnet in 73-109 is a low-Ca pyrope with nearly uniform composition in each grain irrespective | | | Journal (article/letter/editorial) | include garnet and clinopyroxene megacrysts. The pyrope-rich megacrysts can be subdivided in three groups...megacryst mineral species: Mg-ilmenite, diopside, pyrope, zircon, baddeleyite, corundum, Mg-chlorite, kyanite...recovered after the ïŹrst stage of crushing at the mine. Only garnets are available from Kundelungu. The...ppm; Table 1). No trends are observed between the pyrope groups (based on Cr content) and the REE content...not correlate with REE patterns: e.g. a low-Cr pyrope that is LREE-enriched contains inclusions, while | | | Journal (article/letter/editorial) | use only. Bellsbank âą âą .. \ âą 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...clinopyroxene (chromium diop side) 0-20, garnet (chromium pyrope) 0-15, plus variable amounts of chromite and phlogopite...was demonstrated for nodules from Thaba Putsoa (Lesotho) by Boyd & Nixon (1972). The fertile nodules approach | | SOMMER, H., WAN, Y., KRONER, A., XIE, H., JACOB, D. E. (2013) SHRIMP ZIRCON AGES AND PETROLOGY OF LOWER CRUSTAL GRANULITE XENOLITHS FROM THE LETSENG-LA-TERAE KIMBERLITE, LESOTHO: FURTHER EVIDENCE FOR A NAMAQUA-NATAL CONNECTION. South African Journal of Geology, 116 (2) 183-198 doi:10.2113/gssajg.116.2.183 | Journal (article/letter/editorial) | XENOLITHS FROM THE LETSENG-LA-TERAE KIMBERLITE, LESOTHO: FURTHER EVIDENCE FOR A NAMAQUANATAL CONNECTION...granulites of the Letseng-la-Terae Diamond Mine in northeastern Lesotho provide evidence that the Tugela Terrane...PETROLOGY OF LOWER CRUSTAL GRANULITE XENOLITHS, LESOTHO Figure 1. Overview map showing the principal tectonic...location of Letseng-la-Terae Diamond Mine in the eastern part of Lesotho. The map is a modified version and...rocks from the lower crust below northeastern Lesotho exist (Schmitz and Bowring., 2004), these data | | | Report (issue) | cm tall andradite on hematite is from the Wessels Mine near Hotazel in northern Cape Province, South Africa...Cover: Grossular on diopside; 7.1 cm tall Jeffrey Mine, Asbestos, Richmond County, Quebec, Canada Paul...and humorist to this series Facing page: Faceted pyrope-spessartine from Kenya 99.5 carats Houston Museum...DAMERON 52 Classic Garnets: Pyrope BY JOACHIM ZANG AND H. ALBERT GILG 54 Pyrope from the Dora-Maira Massif...fifteen species, six almandine, andradite, grossular, pyrope, spessartine, and uvarovite-are sufficiently abundant | | | Journal (article/letter/editorial) | pressure is required. Therefore, a method to deter mine equilibrium pressure of garnet-clinopyroxene assemblages...1 2 + Mg 3 Al 2 Si 3 O 1 2 â grossular (Gross) pyrope (Pyr) 3CaMgSi 2 O 6 + 3CaAlAlSiO 6 . diopside...is strictly only applicable to assemblages with pyrope-rich garnets (Pyr > 80%). Downloaded by [University...F e )) 2 ]*4.184. (9) For grossular (αGr) and pyrope (αPyr) activities, multicomponent solid-solution...IV-VII by the formulations: (21) (22) 5. The pyrope and grossular activities are deter mined in accordance | | | Journal (article/letter/editorial) | Asia Minor said to be an early gem-cutting center. Pyrope is from the Greek âfireâ or âfiery,â for its color;...at another locality. For example, the formula of pyrope can be written simply as the ideal end-member composition...dark green chromium-rich garnet associated with pyrope in kimberlite. Majorite, Mg,(Fe3+,Si,A1),(Si04)...it is produced by shock (impact) metamorphism. Pyrope, Mg3A1,(Si0,),-a garnet species found only in igneous...minerals âPyralspiteâ group âUgranditeâ group e Pyrope Almandine Spessartine Mg3A1,(Si04), Fe2+,A1,(Si04) | | | Book | The garnets in L2 kimberlite are predominantly pyrope with subsidiary almandine and grossular. Cr203...temperature range 850 to 1450°C for the system enstatite-pyrope and in the presÂŹ sure range 30 to 105 kbar over...Figure 1. The solid solubility of enstatite in pyrope increases gradually to 140 kbar and then suddenly...garnet Iherzolite nodules in kimberlites(from Lesotho and South Africa) and were analysed for isotopic... 1971) the uppermost Drakensberg basalts in Lesotho yielded mica ages of 380, The pipe contains abundant | | | Journal (article/letter/editorial) | recorded in the type Kl kimberlites of the Kao pipe in Lesotho ( Clement, 1973). The cementing mass surrounding...544+0.002 â 11.530±0002 3.50-3.55 U.523+.0.002 Pyrope - 11.622±0.003 Spessartine 98 Pink Diagnosis...their minals gives 50-70% almandine and 25-30% pyrope components. Of the accessory minerals from the...Fe 3 + Mn Mg Ca Na K 3.08 0.01 1.91 Almandine Pyrope Grossular Spessartine Andradite Uvarovite Skiagite...rock-forming garnet (almandine) and a c  cessory pyrope and diamond. These minerals have not so far been | | Grew, E. S., Locock, A. J., Mills, S. J., Galuskina, I. O., Galuskin, E. V., HĂ„lenius, U. (2013) Nomenclature of the garnet supergroup. American Mineralogist, 98 (4) 785-811 doi:10.2138/am.2013.4201 | Journal (article/letter/editorial) | supergroup. The so-called âtetragonal almandine-pyrope phaseâ (TAPP) has the stoichiometry, but not the...GARNET Silicate Menzerite-(Y) Y2Ca Mg2 Si3 O12 Pyrope Mg3 Al2 Si3 O12 Grossular Ca3 Al2 Si3 O12 2+...calcite (white) in the holotype specimen from Wessels Mine, South Africa. Swedish Museum of Natural History...on chromite, from the type locality, Saranovskii Mine, Permskaya Oblast, Middle Urals, Russia. Largest...Menzerite-(Y) {CaY2}[Mg2](Si3)O12 {Y2Ca}[Mg2](Si3)O12 Pyrope Mg3Al2(SiO4)3 {Mg3}[Al2](Si3)O12 Grossular Ca3Al2(SiO4)3 | | | Journal (article/letter/editorial) | mineralogically characterized by lacking chromian pyrope garnet, ilmenite and spinel. YIB1 Kimberlite Macrocrysts...opaque minerals, together with rare nonchromian pyrope garnet. The matrix is composed o f serpentine,...homogeneous in chemical composition and has tool.% of pyrope 32.0, spessartine 1.4, almandine 47.2, grossular.../ oo/ k,o \ v4~ 9 / " Kimberlites(S.Africa & Lesotho) iv / ~ " -- 0.~ ~ / / MgO "~ ~ ~ / w[ Westerl~...imberlit . . . . . v ( .'.Z/'" V (S,Africa&Lesotho) V 'r 50 Wt.% V V ,iths V "~ "~ V ~, FeOtotal | | | Journal (article/letter/editorial) | rights reserved. Keywords: Diamond exploration; Pyrope; Ca-intercept; Peridotite; Megacryst; Eclogite;...peridotite Compositional and phase-relations between Cr-pyrope garnet, chromite and carbon in model peridotite...conditions illustrated, this implies that any Cr-pyrope garnet with Cr/(Cr + Al) greater than line segment...relationship Cr2O3 = 5.0 + 0.94*CaO (in wt.%) for lowCa Cr-pyrope garnet compositions by inspection of experimental... The relations shown in Fig. 1 illustrate that pyrope garnets with Cr/(Cr + Al) less than line segment | | | Journal (article/letter/editorial) | Iherzolite nodules from kimberlitea in northern Lesotho appear to have eq~ibra~d in the upper mantle at...mark the top of the low-velocity zone beneath Lesotho in Late Cretaceous time. INTRODUCTION THE OCCURRENCE...lhe~olite xenoliths from the kimberlites of northern Lesotho. Lherzolites have been selected because they contain...alumina contents of enstatites in eq~~brium with pyrope (~g~~~Si~0~~) and also those in eq~i~b~urn with...Also, contents of enstatites in equilibrium with pyrope in the pure system MgSiOs-MgsAlsSisO,,. The heavy | | 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...et al. (in press) contain subcalcic high-chrome pyrope garnets; however, many fall within the Ca-saturated...of over 200 peridotite xenoliths from the Premier mine, South Africa, yielded 5 graphite-bearing specimens...xenolith is comparable to a lherzolite from Premier Mine containing approximately 60% graphite (Mathias et...Lithology 613C%~ PDB Thaba Putsoa Mothae Thaba Putsoa Kao No. 2 Letseng-la-Terai Jagersfontein Garnet harzburgite |
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