	Stachel, T., Harris, Jeffrey W. (1997) Syngenetic inclusions in diamond from the Birim field (Ghana) - a deep peridotitic profile with a history of depletion and re-enrichment. Contributions to Mineralogy and Petrology, 127 (4) 336-352 doi:10.1007/s004100050284	Journal (article/letter/editorial)
	Harris Syngenetic inclusions in diamond from the Birim ®eld (Ghana) ± a deep peridotitic pro®le with...inclusions from placer deposits (Akwatia mine) along the Birim River, Ghana were studied, thus providing...contents indicate an almost exclusively peridotitic diamond suite, with the vast majority being part of the...harzburgitic paragenesis. Chemically the Akwatian diamond inclusions dier from those in our 1100 sample...observed in an inclusion in diamond. The same garnet also contained a minor enstatite solid-solution component
	Stachel, Thomas, Viljoen, K.Stephanus, Brey, Gerhard, Harris, Jeff W (1998) Metasomatic processes in lherzolitic and harzburgitic domains of diamondiferous lithospheric mantle: REE in garnets from xenoliths and inclusions in diamonds. Earth and Planetary Science Letters, 159 (1) 1-12 doi:10.1016/s0012-821x(98)00064-8	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...(partial melting) originating in the garnet stability field. We suggest that the protolith had undergone polybaric...before being subducted to the depth of the diamond stability field. The growing garnets acquired a depleted
	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 ﬂuid/melt. Mixtures
	De Hoog, J. C. M., Stachel, T., Harris, J. W. (2019) Trace-element geochemistry of diamond-hosted olivine inclusions from the Akwatia Mine, West African Craton: implications for diamond paragenesis and geothermobarometry. Contributions to Mineralogy and Petrology, 174 (12) doi:10.1007/s00410-019-1634-y	Journal (article/letter/editorial)
	Trace‑element geochemistry of diamond‑hosted olivine inclusions from the Akwatia Mine, West African Craton: implications...implications for diamond paragenesis and geothermobarometry J. C. M. De Hoog1 · T. Stachel2 · 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...Conventional geothermobarometry indicates that Akwatia diamonds formed and resided close to a 39 mW/m2
	Stachel, Thomas, Harris, Jeff W. (1997) Diamond precipitation and mantle metasomatism - evidence from the trace element chemistry of silicate inclusions in diamonds from Akwatia, Ghana. Contributions to Mineralogy and Petrology, 129 (2) 143-154 doi:10.1007/s004100050328	Journal (article/letter/editorial)
	Springer-Verlag 1997 Thomas Stachel á Je W. Harris Diamond precipitation and mantle metasomatism ± 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 ¯uids 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 ¯uids with
	Nimis, P. (2002) THE PRESSURES AND TEMPERATURES OF FORMATION OF DIAMOND BASED ON THERMOBAROMETRY OF CHROMIAN DIOPSIDE INCLUSIONS. The Canadian Mineralogist, 40 (3) 871-884 doi:10.2113/gscanmin.40.3.871	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, T., Harris, J.W. (2008) The origin of cratonic diamonds — Constraints from mineral inclusions. Ore Geology Reviews, 34 (1) 5-32 doi:10.1016/j.oregeorev.2007.05.002*	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
	Smit, Karen V., Shirey, Steven B., Wang, Wuyi (2016) Type Ib diamond formation and preservation in the West African lithospheric mantle: Re–Os age constraints from sulphide inclusions in Zimmi diamonds. Precambrian Research, 286. 152-166 doi:10.1016/j.precamres.2016.09.022	Journal (article/letter/editorial)
	homepage: www.elsevier.com/locate/precamres Type Ib diamond formation and preservation in the West African...Available online 22 September 2016 Keywords: Type Ib Diamond Re–Os Sulphide West Africa Cratonic lithosphere...diamonds from the Zimmi (West Africa) alluvial diamond locality were analysed for their bulk Fe–Cu–Ni–Co...features characteristic of eclogitic sulphides. Each diamond has 3–4 individual inclusions. 187Re/188Os and...mineral isochrons for each diamond – unambiguously dating the time of diamond formation. The 650 Ma age
	Nimis, Paolo, Taylor, Wayne R. (2000) Single clinopyroxene thermobarometry for garnet peridotites. Part I. Calibration and testing of a Cr-in-Cpx barometer and an enstatite-in-Cpx thermometer. Contributions to Mineralogy and Petrology, 139 (5) 541-554 doi:10.1007/s004100000156	Journal (article/letter/editorial)
	Calibration and testing of a Cr-in-Cpx barometer and an enstatite-in-Cpx thermometer Received: 16 August 1999 /...used to calibrate a Cr-in-Cpx barometer and an enstatite-in-Cpx thermometer for Cr-diopsides derived from...used Al-in-Opx barometer (2±3 kbar/50 °C). The enstatite-in-Cpx thermometer includes corrections for the...garnet peridotites. P-T estimates obtained for diamond-bearing and graphitebearing lherzolite xenoliths...evaluation of the diamond potential of kimberlite and lamproite provinces and in diamond exploration where
	Stachel, Thomas, Harris, Jeff W., Brey, Gerhard P. (1998) Rare and unusual mineral inclusions in diamonds from Mwadui, Tanzania. Contributions to Mineralogy and Petrology, 132 (1) 34-47 doi:10.1007/s004100050403	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
	Phillips, D., Harris, J.W., Viljoen, K.S. (2004) Mineral chemistry and thermobarometry of inclusions from De Beers Pool diamonds, Kimberley, South Africa. Lithos, 77 (1) 155-179 doi:10.1016/j.lithos.2004.04.005	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) 155–179 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
	*Zhao, Donggao (2022) Electron Probe Microanalysis and Microscopy of Polishing-Exposed Solid-Phase Mineral Inclusions in Fuxian Kimberlite Diamonds. Minerals, 12 (7) 844 doi:10.3390/min12070844*	Journal (article/letter/editorial)
	Abstract: Solid-phase mineral inclusions in diamond (1–3 mm in diameter) from the No. 50 kimberlite...carbonate and sulfide inclusions were recovered in the diamond. The common solid-phase inclusions are olivine...and composition of the solid-phase inclusions in diamond indicate that they belong to the peridotitic suite...eclogitic mineral inclusions were found in the diamond. The slightly lower Mg # of the olivine inclusions...to 0.79 wt. %) in some chromite inclusions in diamond than those in chromite inclusions worldwide, the
	Wijbrans, C. H., Rohrbach, A., Klemme, S. (2016) An experimental investigation of the stability of majoritic garnet in the Earth’s mantle and an improved majorite geobarometer. Contributions to Mineralogy and Petrology, 171 (5) doi:10.1007/s00410-016-1255-7	Journal (article/letter/editorial)
	Switzerland Keywords Majorite · Garnet · Chromium · Diamond inclusions · Depleted mantle · Transition zone...series of high-pressure phase transformations: Enstatite (MgSiO3 pyroxene) or its high-pressure polymorphs...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...transformation reaction between pyrope (Mg3Al2Si3O12) and enstatite (MgSiO3) may be described as Eclogite 10 te
	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
	*(2012, April) Gems & Gemology* Vol. 48 (1) Gemological Institute of America**	Journal (issue)
	Precision Measurement of Facet Angles Vallerano Diamond from Ancient Rome Radioactive Morganite Because...Points 18 pg. 3 Emeralds from the Fazenda Bonfim Region, Rio Grande do Norte, Brazil J. C. (Hanco) Zwaan...Sally Eaton-Magaña The ultrathin coating on this diamond simulant contains nanoparticles that could not...diamonds to very high precision. 39 The Vallerano Diamond from Ancient Rome: A Scientific Study Alessandro...Anna Rapinesi, and Diego Sali An ancient Roman diamond ring, excavated during the 1990s, underwent gemological
	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 ‘‘epicenter’’ of diamond exploration and mining, including a series of kimberlite
	*Wilson, A. N. (1982) Diamonds* - from Birth to Eternity. Gemological Institute of America, Santa Monica, CA.**	Book
	Coast. DIAMONDS: FROM BIRTH TO ETERNITY A diamond is rarely found embedded in kimberlite rock. This...update its diamond mining and reeovery inlormation, we asked the assistance ol John Roux, Diamond Information...to present Arthur Wilson’s compilation on the diamond and its origins. Richard T. Liddicoat, Jr. CONTENTS... 413 Index . 449 i\ LIST OF ILLUSTRATIONS Diamond (Color Plate).Frontispiece Lord Rutherford. 4 Radiometric...Radiometric dating. 5 Hannay's experiment. 11 Graphite-diamond equilibrium . 13 Convection cells . 15 Snider-Pelligrini
	Creighton, Steven, Stachel, Thomas, Eichenberg, Dave, Luth, Robert W. (2010) Oxidation state of the lithospheric mantle beneath Diavik diamond mine, central Slave craton, NWT, Canada. Contributions to Mineralogy and Petrology, 159 (5) 645-657 doi:10.1007/s00410-009-0446-x	Journal (article/letter/editorial)
	state of the lithospheric mantle beneath Diavik diamond mine, central Slave craton, NWT, Canada Steven Creighton...A154-North and A154-South kimberlites of the Diavik diamond mine using the newly developed flank method modified...e-mail: Robert.Luth@ualberta.ca D. Eichenberg Diavik Diamond Mines Inc., Yellowknife, Canada Present Address:...state of the Diavik mantle sample suggests that diamond formation occurred by reduction of carbonate by...Davis 1999) showing the location of the Diavik diamond mine in the Lac de Gras area of the central portion
	Wijbrans, C. H., Niehaus, O., Rohrbach, A., Pöttgen, R., Klemme, S. (2014) Thermodynamic and magnetic properties of knorringite garnet (Mg3Cr2Si3O12) based on low-temperature calorimetry and magnetic susceptibility measurements. Physics and Chemistry of Minerals, 41 (5) 341-346 doi:10.1007/s00269-013-0653-x	Journal (article/letter/editorial)
	particular, Cr-rich garnets are commonly found in diamond inclusions and in deep-seated mantle xenoliths...often found in diamond-bearing mantle xenoliths and are also used as a so-called diamond indicator mineral...mineral in the diamond exploration industry (Cookenboo and Grutter 2010). However, the stability of Cr-bearing...starting composition that contained knorringite, enstatite and unreacted eskolaite (Cr2O3) was mixed into...magnetic field strength of 10 kOe. The inset shows the magnetic susceptibility in zero-field- (ZFC) and
	Anjos, Camila Wense Dias Dos, Meunier, Alain, Guimarães, Edi Mendes, el Albani, Abderrazzak (2010) Saponite-rich black shales and nontronite beds of the Permian Irati Formation: sediment sources and thermal metamorphism (Paraná basin, Brazil) Clays and Clay Minerals, 58 (5) 606-626 doi:10.1346/ccmn.2010.0580503	Journal (article/letter/editorial)
	effect is confirmed by the presence of secondary enstatite-augite and albite crystals. Key Words—Ash Fall...large intracratonic basin located in the central eastern part of the South America Platform (Figure 1)....the states of Goiás and Mato Grosso). In this region, the dolostone levels of the Assistência Member...saponite; T: talc. long, euhedral pyroxene crystals (enstatite-augite) dispersed in the matrix (Dos Anjos, 2003)...(Figure 7a). The 3675 cm 1 band (OH-stretching region, Figure 8) indicates the presence of 3Mg-OH groups
	Promprated, Prinya, Taylor, Lawrence, Floss, Christine, Malkovets, Vladimir, Anand, Mahesh, Griffin, William, Pokhilenko, Nikolai, Sobolev, Nikolai (2003) Diamond Inclusions from Snap Lake, Nwt Canada, 8th International Kimberlite Conference Long Abstract. 1-5	Other Paper
	DIAMOND INCLUSIONS FROM SNAP LAKE, NWT CANADA Prinya Promprated1, Lawrence Taylor1, Christine Floss2...Slave craton of Canada has been recognized for its diamond potential, with the discovery of diamondiferous...subsequently identified, some with great potential for diamond-bearing. The scientific interest resulting from...Slave craton (Fig. 1), are diamond-bearing, and arguably the largest diamond deposit yet discovered on...of which the majority of DIs are olivine and enstatite, with small numbers of pyrope, chromite, clinopyroxene
	*Simakov, S.K. (2008) Garnet–clinopyroxene and clinopyroxene geothermobarometry of deep mantle and crust eclogites and peridotites. Lithos, 106 (1) 125-136 doi:10.1016/j.lithos.2008.06.013*	Journal (article/letter/editorial)
	inclusions in diamonds, diamondbearing, diamond–graphite-bearing and diamond-free eclogites and peridotites from...phases such as kyanite, corundum, graphite or diamond are few. The investigation of such xenoliths provides...on average 50% of the total mineral activity, enstatite 20% and pyrope and grossular are 15% each. The...average of 10% of the total mineral activity, enstatite 16% and pyrope and grossular are 5% each. The...Inclusions in diamonds and diamond-bearing xenoliths mainly plot in the region corresponding to the 2.4
	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...element patterns for garnet inclusions indicate diamond precipitation under sub-solidus (lherzolite + H2O)...conditions. This conclusion links the presence of a diamond-rich lherzolitic layer in the lithospheric mantle...melt at depths >140 km. Keywords Inclusion in diamond . Garnet lherzolite . Geothermobarometry . Nitrogen
	Wang, Wuyi, Gasparik, Tibor (2001) Metasomatic clinopyroxene inclusions in diamonds from the Liaoning Province, China. Geochimica et Cosmochimica Acta, 65 (4) 611-620 doi:10.1016/s0016-7037(00)00553-6	Journal (article/letter/editorial)
	the source of carbon for the crystallization of diamond. Considering the large variations in mineral chemistry...Calibration of the Cr-incpx barometer and the enstatite-in-cpx thermometer by Nimis and Taylor (2000)... These conditions are well inside the diamond stability region, and are close but slightly below the...affect the REE concentrations in cpx at the diamond stability region: the bulk REE concentrations in the host...cpx has not been entirely molten in the diamond stability region, cpx and garnet are the two main REE repositories
	*(2020) The Journal of Gemmology* Vol. 37 (2) Gem-A**	Journal (issue)
	2020 COLUMNS What’s New 115 CIBJO Blue Books \| Diamond Terminology Guidelines \| GemGuide Articles \| GIT...Aquamarine with Spodumene Inclusions from the Oceanview Mine, California, USA \| Demantoid/ Andradite Slices from...Terrence S. Coldham Emmanuel Fritsch HONORARY DIAMOND MEMBER Martin Rapaport CHIEF EXECUTIVE OFFICER...the-blue-books-2. Diamond Terminology Guidelines In September 2019, the Diamond Producers Association...Association, in conjunction with seven other leading diamond industry organisations, issued a brief reference

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Enstatite from Akwatia Mine, Birim diamond field, Denkyembour District, Eastern Region, Ghana

Enstatite from
Akwatia Mine, Birim diamond field, Denkyembour District, Eastern Region, Ghana