 | | Journal (article/letter/editorial) | | Comparison with inclusions in diamonds from Akwatia (Ghana) shows that there are no significant differences...lherzolitic garnets from Roberts Victor (nodules) and Akwatia (diamonds) were crystallised from precursor rocks...depletion by partial melting in the spinel stability field which resulted in high Cr=Al in the residue. Harzburgitic...elements for southern African garnet harzburgite and lherzolite xenoliths [F.R. Boyd, Earth Planet. Sci. Lett...(partial melting) originating in the garnet stability field. We suggest that the protolith had undergone polybaric |  | | Journal (article/letter/editorial) | | Springer-Verlag 1997 Thomas Stachel Ć” JeĀ W. Harris Diamond precipitation and mantle metasomatism Ā± evidence...chemistry of silicate inclusions in diamonds from Akwatia, Ghana Received: 27 January 1996 / Accepted: 5 May...clinopyroxene) included in diamonds from Akwatia (Birim Field, Ghana) were determined using SIMS. Incompatible...CO2bearing melts or ĀÆuids may thus be excluded. Diamond inclusion chemistry and mineralogy also is inconsistent...metasomatism by H2O-rich melts. We therefore favour diamond precipitation by oxidation of CH4-rich ĀÆuids with |  | | Journal (article/letter/editorial) | | Traceāelement geochemistry of diamondāhosted olivine inclusions from the Akwatia Mine, West African Craton: implications...implications for diamond paragenesis and geothermobarometry J. C. M. De Hoog1 Ā· T. Stachel2 Ā· J. W. Harris3...coexisting garnets included in diamonds from the Akwatia Mine (Ghana, West African Craton) were measured to show...similar information about equilibration temperature, diamond paragenesis and mantle processes as garnet. Trace-element...olivines from lherzolite ones: if Ca/Al ratios of olivine are below the mantle lherzolite trend (Ca/Al |  | Melton, G.L., McNeill, J., Stachel, T., Pearson, D.G., Harris, J.W. (2012) Trace elements in gem diamond from Akwatia, Ghana and DeBeers Pool, South Africa. Chemical Geology, 314. 1-8 doi:10.1016/j.chemgeo.2012.04.025 | Journal (article/letter/editorial) | | Research paper Trace elements in gem diamond from Akwatia, Ghana and DeBeers Pool, South Africa G.L. Melton...ICPMS Ghana De Beers Pool a b s t r a c t Monocrystalline gem-quality diamonds from Akwatia, Ghana and...elevated LREEN/MREEN and variable LREEN/TiN. One diamond from Ghana is distinct (G103) by having a much steeper...Syngenetic garnet inclusions indicate that the diamond growth medium must have been highly enriched in...trace impurities in gem diamond represent trapped inclusions of the diamond forming ļ¬uid/melt. Mixtures |  | | Journal (article/letter/editorial) | | equal importance as source rocks, followed by lherzolite and websterite. Diamonds which provide evidence...formation event documented on the worldās major diamond producing cratons occurs in Archean lithospheric...diamonds, G10 garnets, and diamond inclusion-type chromites, well used in diamond exploration. Within the...mantle domains of diamond stability, there have been repeated episodes of further diamond crystallization...peridotite. Using improved methods of isotope analysis, diamond formation ages can be correlated with specific |  | (Fanus) Viljoen, K.S., Dobbe, RenĆ©, Smit, Braam, Thomassot, Emilie, Cartigny, Pierre (2004) Petrology and geochemistry of a diamondiferous lherzolite from the Premier diamond mine, South Africa. Lithos, 77 (1) 539-552 doi:10.1016/j.lithos.2004.03.023 | Journal (article/letter/editorial) | | geochemistry of a diamondiferous lherzolite from the Premier diamond mine, South Africa K.S. (Fanus) Viljoen...diamondiferous peridotite xenolith from the Premier diamond mine in South Africa. The xenolith is altered with...element pattern similar to garnet from fertile lherzolite. All diamonds recovered are colourless. Most...6 x to 1.3x. These are broadly correlated with diamond nitrogen content as determined by infrared spectroscopy...It is concluded that the xenolith is a fertile lherzolite, and that the lherzolitic character may have |  | | Journal (article/letter/editorial) | | silicate phases by a metasomatic agent during diamond formation unlike other trace elements like REE...rights reserved. Keywords: Lithium; Inclusions in diamond; Eclogites; Peridotites; Websterites; Majorite...chemgeo.2003.08.001 ed at the time and place of diamond formation and carry information on the chemistry...signatures of diamonds and their inclusions unravelled diamond formation processes, the magmatic, metamorphic...incompatible elements presumably at the time of diamond formation (e.g., Stachel et al., 2000a,b and references |  | | Journal (article/letter/editorial) | | 2007 Available online 22 April 2008 Keywords: Diamond formation Peridotitic Eclogitic Websteritic Subcratonic...suites and used to establish the characteristics of diamond source rocks in the subcratonic lithospheric mantle...(Kalahari Craton) is by far the best studied diamond source region in the world but appears to be unique rather...and trace element characteristics of peridotitic diamond sources indicate polybaric melt extraction proceeding...mounting evidence from xenolith studies, eclogitic diamond sources are linked to subducted oceanic protoliths |  | | Journal (article/letter/editorial) | | inclusions in alluvial diamonds from the Kankan region of Guinea in West Africa are mainly of lherzolitic...exclusively lherzolitic garnets document that the diamond source experienced a previous stage of melt extraction...from the Monastery mine. Subsequently, the discovery of diamonds from the Brazilian mine SaĆo Luiz, which...the present study on diamonds from the Kankan district in Guinea, we will examine the major and trace...lithospheric inclusion parageneses and then evaluate diamond populations derived from the asthenosphere and |  | | Journal (article/letter/editorial) | | THE PRESSURES AND TEMPERATURES OF FORMATION OF DIAMOND BASED ON THERMOBAROMETRY OF CHROMIAN DIOPSIDE INCLUSIONS...temperature (T) and pressure (P) of formation of natural diamond has generally relied on thermobarometry of rare...potential re-equilibration of touching minerals after diamond growth and possible disequilibrium between non-touching...inclusions of chromian diopside (mostly isolated) in diamond crystals containing inclusions of peridotitic material...conditions and relative timing of diamond genesis. Inclusions in diamond and xenoliths from the same source |  | Stachel, Thomas, Aulbach, Sonja, Brey, Gerhard P., Harris, Jeff W., Leost, Ingrid, Tappert, Ralf, Viljoen, K.S.(Fanus) (2004) The trace element composition of silicate inclusions in diamonds: a review. Lithos, 77 (1) 1-19 doi:10.1016/j.lithos.2004.03.027 | Journal (article/letter/editorial) | | relations are not linear, but it appears that lherzolite style enrichment in MREE ā HREE only occurs at...eclogitic diamond sources. The trace element composition of an āāaverage eclogitic diamond sourceāā based...about 10% of a partial melt in the garnet stability field and that subsequently experienced only minor reenrichment...inclusion. This suggests that sublithospheric diamond sources may be linked to old oceanic slabs, possibly...can provide the redox gradients necessary for diamond precipitation in an otherwise reduced sublithospheric |  | | Journal (article/letter/editorial) | | Akademika Osipāyana 4, Chernogolovka, 142432, Moscow Region, Russia b Science Facilities Department, Natural...set of trace elements (TE) in the partly molten diamond-forming peridotiteāeclogiteā carbonatite system...Model TE partition coefficients for the natural diamond-producing carbonatite melts of mantle chambers...minerals of peridotite and eclogite parageneses of diamond inclusions, on the one hand, and on the experimental...āmetasomatic agentsā in the formation of chambers of diamond-forming carbonatite magmas. Ā© 2015, V.S. Sobolev |  | | Journal (article/letter/editorial) | | 0 Ga) and hence an unconventional setting for diamond exploration. Buffalo Hills diamonds formed during...2006 Elsevier B.V. All rights reserved. Keywords: Diamond inclusions; Carbon isotopes; Nitrogen aggregation;...Majorite; Off-craton 1. Introduction Traditionally diamond exploration has focused on cratons stabilized in...an empirically derived association of primary diamond deposits with Archean cratons as summarized by...in the discovery of the Buffalo Hills kimberlite field in northern Alberta. It was discovered in 1997 by |  | | Journal (article/letter/editorial) | | Accepted: 7 January 1998 Abstract Syngenetic diamond inclusions from the Mwadui kimberlite reveal that...pairs suggests successive iron enrichment during diamond formation, e.g. leading to the presence of harzburgitic...harzburgitic garnet and lherzolitic olivine in the same diamond. Apart from the dominant peridotitic inclusion...association Fe-FeO-Fe3O4 in one single diamond indicates diamond formation over a large range of fO2 conditions...harzburgitic garnet and a SiO2-phase in the same diamond. Alternatively the formation of the SiO2phase may |  | Taylor, Lawrence A., Anand, Mahesh, Promprated, Prinya, Floss, Christine, Sobolev, Nikolai V. (2003) The significance of mineral inclusions in large diamonds from Yakutia, Russia. American Mineralogist, 88 (5) 912-920 doi:10.2138/am-2003-5-621 | Journal (article/letter/editorial) | | and eclogitic groups, in addition to chromite diamond inclusions (DIs). The most striking feature of...DIs involved complex processing prior to their diamond encapsulation. That is, the garnet DIs retained...retained a signature of their earlier, pre-diamond encapsulation history. This result is taken as proof that...protogenetic) with their host diamonds. INTRODUCTION Diamond inclusions (DIs) provide a unique set of mantle...chemical variations among inclusions within a single diamond, thereby addressing the co-genesis of the diamonds |  | | Journal (article/letter/editorial) | | from fertile pyrolite to refractory, high-Cr lherzolite. The barometer is based on the Cr exchange between...P-T estimates obtained for diamond-bearing and graphitebearing lherzolite xenoliths and peridotitic clinopyroxene...evaluation of the diamond potential of kimberlite and lamproite provinces and in diamond exploration where...an indicator mineral that can be used to locate diamond-bearing pipes (Sobolev 1977; Ramsay 1992; Fipke...1995). However, not all Cr-diopside recovered in diamond exploration programs is likely to be of high-pressure |  | | Journal (article/letter/editorial) | | 2004 Elsevier B.V. All rights reserved. Keywords: Diamond; Inclusion; Peridotite; Mantle metasomatism; REE;...characteristics of both peridotitic and websteritic diamond sources (Leost Inclusions were released by crushing...1997a; Stachel et al., 2000). The compositional field for lherzolitic garnets is from Sobolev et al. (1973)...(Cr2O3 of 2.6 ā 17.3 wt.%) of garnets is rare among diamond sources worldwide, and on the Kalahari Craton,...olivine coexists with clinopyroxene in the same diamond (Nam-51B, Table 2) and two more olivines have similarly |  | | Journal (article/letter/editorial) | | 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...Thermobarometry; De Beers Pool inclusions 1. Introduction Diamond provides an impermeable barrier that can insulate...sub-continental mantle lithosphere at the time of diamond formation. Most inclusions can be sub-divided into...temperature/pressure conditions and/or unique environments of diamond formation (e.g. Taylor et al., 1996; Sobolev et |  | Cartigny, Pierre, Farquhar, James, Thomassot, Emilie, Harris, Jeffrey W., Wing, Bozwell, Masterson, Andy, McKeegan, Kevin, Stachel, Thomas (2009) A mantle origin for Paleoarchean peridotitic diamonds from the Panda kimberlite, Slave Craton: Evidence from 13C-, 15N- and 33,34S-stable isotope systematics. Lithos, 112. 852-864 doi:10.1016/j.lithos.2009.06.007 | Journal (article/letter/editorial) | | Stable isotopes Diamond Continental lithosphere a b s t r a c t In order to address diamond formation and...from lower mantle) from the Panda kimberlite (Ekati Mine, Lac de Gras Area, Canada). For 12 peridotitic and...sulļ¬debearing diamonds should be considered as a speciļ¬c diamond population on a global-scale. Based on our study...can actually be well-crystallised and non-ļ¬brous diamond, c.f. Moore,1985). Eclogite xenoliths from the...mantle formation beneath the Slave. Furthermore, diamond formation as well differ beneath the two cratons |  | Stachel, Thomas, Banas, Anetta, Aulbach, Sonja, Smit, Karen V., Wescott, Pamela, Chinn, Ingrid L., Kong, Julie (2018) The Victor Mine (Superior Craton, Canada): Neoproterozoic lherzolitic diamonds from a thermally-modified cratonic root. Mineralogy and Petrology, 112. 325-336 doi:10.1007/s00710-018-0574-y | Journal (article/letter/editorial) | | 1007/s00710-018-0574-y ORIGINAL PAPER The Victor Mine (Superior Craton, Canada): Neoproterozoic lherzolitic...Abstract The Jurassic Victor kimberlite (Attawapiskat Field) was emplaced into an area of the central Superior...garnet inclusions indicate diamond precipitation under sub-solidus (lherzolite + H2O) conditions. This conclusion...conclusion links the presence of a diamond-rich lherzolitic layer in the lithospheric mantle, just above...along an average cratonic geotherm (40 mW/m2) lherzolite in the presence of hydrous fluid would melt at |  | | Journal (article/letter/editorial) | | Switzerland Keywords Majorite Ā· Garnet Ā· Chromium Ā· Diamond inclusions Ā· Depleted mantle Ā· Transition zone...peridotites (for instance in the Western Gneiss region of Norway), samples are found which contain garnets...(Haggerty and Sautter 1990). While rare, majoritic diamond inclusions are reported from cratons all over the...websteritic. A number of majoritic garnets from diamond inclusions are also plotted in the diagram (for...interpretation for the origin of the deep eclogitic diamond inclusions is that they are derived from subducted |  | Banas, A., Stachel, T., Phillips, D., Shimizu, N., Viljoen, K.S., Harris, J.W. (2009) Ancient metasomatism recorded by ultra-depleted garnet inclusions in diamonds from DeBeers Pool, South Africa. Lithos, 112. 736-746 doi:10.1016/j.lithos.2009.04.043 | Journal (article/letter/editorial) | | April 2009 Available online 6 June 2009 Keywords: Diamond inclusion Trace elements REE Metasomatism Paleoarchean...area and strongly underlines the unique role that diamond may play as a time capsule. Analyses of rare earth...and Fe), affected only a portion of the diamond source region and was restricted to comparatively shallower...shallower lithosphere at depths b180 km. Diamond precipitation was likely associated with both styles of...constrained the pressureātemperature conditions of diamond formation beneath the Kimberley area based on an |  | Krebs, M.Y., Pearson, D.G., Stachel, T., Laiginhas, F., Woodland, S., Chinn, I., Kong, J. (2019) A common parentage-low abundance trace element data of gem diamonds reveals similar fluids to fibrous diamonds. Lithos, 324. 356-370 doi:10.1016/j.lithos.2018.11.025 | Journal (article/letter/editorial) | | data from high-purity gem diamonds from the Victor Mine, Ontario, Canada as well as near- gem diamonds from...signature indicative of original derivation of the diamond forming agent AC during major melting (~10 %...Keywords: Trace Elements; Diamond; Laser ablation; diamond HDFs; Victor diamond mine ACCEPTED MANUSCRIPT...MANUSCRIPT 1. Introduction Diamond crystallizes from a fluid/melt phase - relics of which may become trapped and...Weiss et al., 2009). M Trace element patterns of diamond HDFs have been classified into two end-members: |  | Promprated, Prinya, Taylor, Lawrence A., Anand, Mahesh, Floss, Christine, Sobolev, Nikolai V., Pokhilenko, Nikolai P. (2004) Multiple-mineral inclusions in diamonds from the Snap Lake/King Lake kimberlite dike, Slave craton, Canada: a trace-element perspective. Lithos, 77 (1) 69-81 doi:10.1016/j.lithos.2004.04.009 | Journal (article/letter/editorial) | | As observed worldwide, the harzburgitic-garnet diamond inclusions (DIs) possess sinusoidal REE patterns...inclusion that occurs at the outer portion of a diamond compared to that near the core. The compositions...B.V. All rights reserved. Keywords: Snap Lake; Diamond inclusions; Trace element; REE; In situ analysis;...history of diamond inclusions (DIs) is crucial to understanding the processes involved in diamond formation...the Slave craton has become the āāepicenterāā of diamond exploration and mining, including a series of kimberlite |  | | Journal (article/letter/editorial) | | octahedral diamond from Finsch, South Africa and in the MC octahedral core of a coated diamond from Kankan...nitrogen in B-centers. Numerous microinclusions in diamond Finsch_2a_cap1 are restricted to two thin layers...parallel to the (1 1 1) face, 20 and 200 lm from the diamond rim. Low-Mg carbonatitic HDFs are found along the...inclusion in the center of the octahedral core of diamond ON-KAN-383. This evidence for the involvement of...the similarity of trace element pattern of a MC diamond to those of low-Mg carbonatitic HDF in ļ¬brous diamonds |
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