DOCSLIB.ORG

A New Deposit of Gem-Quality Grandidierite in Madagascar

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
A New Deposit of Gem-Quality Grandidierite in Madagascar NO ES & NEW TECHNIQUES A NEW DEPOSIT OF GEM-QUALITY GRANDIDIERITE IN MADAGASCAR Delphine Bruyère, Claude Delor, Julien Raoul, Rufin Rakotondranaivo, Guillaume Wille, Nicolas Maubec, and Abdeltif Lahfid Since its discovery, grandidierite has been found as A new deposit of grandidierite, considered one a rare accessory mineral in aluminous boron-rich peg- of the world’s rarest gems, has been discovered matite; in aplite, gneiss, and crystalline rock associ- in southern Madagascar. The new deposit is out- ated with charnockite; and in rock subjected to local side the town of Tranomaro, near the original lo- high-temperature, low-pressure metamorphism (con- cality of Andrahomana. It occurs in the form of tact aureoles and xenoliths). In addition to Madagas- strong bluish green to greenish blue translucent car, it has been reported from New Zealand (Black, to transparent crystals measuring up to 15 × 7 × 1970), Norway (Krogh, 1975), Suriname (de Roever and 3 cm. Grandidierite is the magnesium end mem- Kieft, 1976), Algeria (Fabriès et al., 1976), Italy (van ber in the solid-solution series with ominelite as Bergen, 1980), Malawi (Haslam, 1980), India (Grew, the iron end member. The studied samples have 1983), the United States (Rowley, 1987; Grew et al., a very low Fe/(Mg + Fe) ratio. This confirms that 1991), Canada (Lonker, 1988), Antarctica (Carson et the Tranomaro deposit, together with Johnsburg al., 1995), the Czech Republic (Cempírek et al., 2010), in New York State, provides the purest grandi- and other localities. Yet gem-quality grandidierite is dierite ever found. The crystals host inclusions of extremely rare. Facetable gem material larger than a Cl-apatite, zircon, and monazite.The paragenesis millimeter has only been found in Madagascar and Sri also includes plagioclase, phlogopite, enstatite, Lanka; the latter is the source of a clean faceted spec- diopside, dravite, and sapphirine (locally as gem- imen weighing 0.29 ct (Schmetzer et al., 2003). quality crystals). Transparent crystals have been faceted, yielding small but eye-clean jewelry- quality gems. Figure 1. This 0.11 ct round brilliant grandidierite is from a new deposit near the town of Tranomaro, in southern Madagascar. Photo by Delphine Bruyère. amed after French naturalist Alfred Grandidier (1836–1912), grandidierite is an extremely rare orthorhombicN Mg-Fe aluminous borosilicate with the formula (Mg,Fe)Al (BO )(SiO )O (Lacroix, 1902, 3 3 4 2 1922a,b). The material was first discovered at the cliffs of Andrahomana, on the southern coast of Madagascar. Grandidierite is described as a bluish green to greenish blue mineral (figure 1); the blue component increases with Fe content. It is transpar- ent to translucent with a pale yellow to colorless, greenish blue, and blue trichroism. The larger elon- gate euhedral orthorhombic crystals, which may measure up to 8 cm, are often strongly corroded. See end of article for About the Authors and Acknowledgments. GEMS &G EMOLOGY, Vol. 52, No. 3, pp. 266–275, http://dx.doi.org/10.5741/GEMS.52.3.266 © 2016 Gemological Institute of America 266 NOTES & NEW TECHNIQUES GEMS & GEMOLOGY FALL 2016 D Sedimentary rocks N Vohibory Domain -D Androyan Domain Anosyan Domain D MADAGASCAR D Magmatic Androy Massif Ihosy Magmatic Ambalavao suite D 1 RANOTSARA Shear zones • ~ • Grandidierite-bearing localities Figure 2. A map of SHEAR ZONE Madagascar south of the Ranotsara shear zone showing the loca- tion of grandidierite- bearing deposits. 1: Ihosy, 2: Esira, 3: Vohi- bola, 4: Nampoana, 5: BETROKA BELT Andrahomana, 6: Tra- nomaro (this study). Modified after Razaka- BEKILY BELT manana et al. (2010) TRANOMARO BELT and Roig et al. (2012). Androy 2 VOHIBORY BELT Massif • Mahafaly Plateau Anosy Mountains 6 Ampanihy • FORT DAUPHIN BELT 3 • 4 Androhondroho Plateau • Tolanaro •5 Cape Andrahomana Karimbola Plateau 0 50 km The type locality described by Lacroix (1902) was GEOLOGICAL BACKGROUND visited in 1960 by C. Mignot, who was unable to find The crystalline bedrock of Madagascar is described additional grandidierite at the site (Béhier, 1960a,b), in terms of six geodynamic blocks that define the as the small pegmatite was depleted. Since then, constituent elements of the Precambrian Shield; grandidierite has been reported in a few other locali- these are, from southwest to northeast, the Vohibory, ties in southern Madagascar that have also since been Androyan-Anosyan, Ikalamavony, Antananarivo, depleted. The present study focuses on a new deposit Antongil-Masora, and Bemarivo domains. As the re- discovered in May 2014 near Tranomaro, close to the sult of a major five-year (2007–2012) study funded by original locality of Andrahomana (figure 2). The aim the World Bank, the Precambrian geology of Mada- of this study is to determine the material’s properties gascar has been reinterpreted. The Antongil-Masora and to evaluate its gem potential. and Antananarivo domains are now considered part NOTES & NEW TECHNIQUES GEMS & GEMOLOGY FALL 2016 267 of an even larger craton—the Greater Dharwar cra- Tolanaro (Farges, 2001) and at Sakatelo, Ampamatoa, ton—that encompassed part of present-day India and Marotrana, and Sahakondra, near Esira (McKie, 1965; Madagascar and was consolidated approximately Farges, 2001). It was also found in association with 2.45–2.5 billion years ago (Tucker et al., 2012). The serendibite and tourmaline in anatectic gneiss near Ranotsara shear zone marks the approximate bound- Ihosy (Nicollet, 1990). These reports relate only mi- ary between the Archean crust to the north and a croscopic crystals of grandidierite, and the Lacroix more recent basement to the south. The Androyen- finding from a century ago remains the only one of Anosyen domain of southern Madagascar is indeed a gemological interest. Grandidierite was recently re- continental terrane of Paleoproterozoic age (1.8–2.0 ported from a mine near Tolanaro, with no further in- billion years ago). It was accreted to the Vohibory do- formation yet (Vertriest et al., 2015). main, an oceanic terrane of early Neoproterozoic age, in Cryogenian time (about 0.62–0.64 billion years LOCATION AND MINING ago). A first deformation (600–650 Ma) gave rise to A new deposit of grandidierite was discovered in May recumbent isoclinal folds and a regional shallow-dip- 2014 by two of the authors and their mining team, ping foliation, with a second deformation (500–530 about 15 km from the village of Tranomaro. The area Ma) producing steep north-south-trending shear is located in the Amboasary district of southern zones that separate five gneissic tectonic belts. The Madagascar’s Anosy region (again, see figure 2), 60 last episode of Madagascar’s Neoproterozoic geody- km northwest of Cape Andrahomana. Access from namic evolution is marked by the alkaline magma- Tolanaro is via a 60 km paved road west to Am- tism of the Ambalavao suite, which forms major boasary Atsimo, followed by a rough, unpaved 50 km batholitic intrusions (up to 1400 km²). Numerous road north to Tranomaro that requires a four-wheel- pegmatitic vein intrusions associated with this drive vehicle. Final access from the village of Tra- episode are directly related to gem and rare earth el- nomaro to the deposit is half a day by foot only. ement (REE) mineralization. A final magmatic activ- Security is a problem because bandits operate throughout the region. Mining is done by hand due to the locality’s re- mote location, its limited production, and its irregu- In Brief lar, discontinuous veins in opposition to large linear • A new deposit of gem-quality grandidierite was discov- veins. The deposit itself extends over a few acres. ered in May 2014 in southern Madagascar. The weathered pegmatite is exploited by near-surface • The very low Fe/(Mg + Fe) ratio makes these crystals, artisanal and small-scale mining (figure 3). Using together with samples from Johnsburg in New York spades and pickaxes, about 12 miners dig holes up to State, the purest grandidierite ever found. a depth of 15 meters. These open-air corridors cross- • The ratio of gem-quality crystals is about 1 in 10,000. cut two grandidierite-bearing veins separated by 30 • A few dozen rough transparent crystals have been cm to a few meters. The uppermost tunnel is called faceted, yielding small but eye-clean jewelry-quality “Vein 1,” while the deeper one is “Vein 2.” The gems, including fewer than 10 that are above 1 carat. rough blue crystals are manually extracted and sorted on-site. The workers carefully remove the valuable mineral specimens to avoid damaging them. Be- ity during the Cretaceous period is expressed by the tween May 2014 and March 2016, 800 kg of rough megavolcanic Androy Massif. specimens were produced. Mining is still in progress A grandidierite-bearing pegmatite is found in the as of this writing. Anosyan domain (again, see figure 2). At Cape Andra- homana, where grandidierite was first described, it MATERIALS AND METHODS was associated with quartz, microcline, red alman- Using standard gemological methods, we tested a dine, pleonaste, andalusite, and biotite in a pegmatite dozen grandidierite crystals from the two veins near and an aplite (Lacroix, 1922a,b). Grandidierite was also Tranomaro for pleochroism, fluorescence reaction, found 30 km to the north, near Vohibola, in associa- and specific gravity at the French Geological Survey tion with serendibite and sinhalite in a diopsidite- (BRGM) in Orléans, France. After the samples were bearing paragneiss (Razakamanana et al., 2010). It was prepared as polished thin sections, we observed them associated with quartz in the Nampoana quarry near under a polarizing microscope. The crystals’ chemi- 268 NOTES & NEW TECHNIQUES GEMS & GEMOLOGY FALL 2016 Figure 3. At the new deposit in Madagascar, grandidierite is exploited by artisanal and small-scale mining (left), and rough crystals are sorted on-site (right). Photos by Rufin Rakotondranaivo. cal homogeneity was investigated with a scanning 6° to 75° 2 on a Bruker D8 Advance diffractometer θ electron microscope (SEM) on sections that had been with Cu-K radiation ( =1.5418 Å, 40 kV, and 40 α λ carbon coated under vacuum (approximately 20 nm mA) and a Lynx-Eye 1D detector, using a step size of thick).
Load more

Recommended publications
  • Compte Rendu Final D'execution De Projet
    COMPTE RENDU FINAL D’EXECUTION DE PROJET I. INFORMATIONS DE BASE Nom de l’organisation : Centre Ecologique de Libanona Titre du projet : Community Forest Management of the Tandroy Forests of Southern Madagascar Dates de projet (comme indiqué dans l'accord) : le 1 novembre 2002 – le 30 avril 2004 Date du rapport (mois/annéé): Août 10, 2005 II. REMARQUES PRÉLIMINAIRES Fournir toute remarque préliminaire susceptible d’aider à l’examen de ce compte rendu. I- Remarques Initially the concept of the project had been to work across 4 of the sub-prefectures of Androy (Amboasary, Ambovombe, Tsiombe, Beloha), however at the outset of the implementation phase of this project several factors dictated that the work be limited to the subprefecture nearest to Fort Dauphin, namely Amboasary where the project team worked in 4 communes. (These mitigating factors included a prolonged drought in the Central and Western parts of Androy, lack of capacity in the forest service personnel in the central and western part of Androy and diminished logistical support from the major project partner WWF (due to the scaling down of their Ala Maiky Programme)). Additionally to this change the project over-ran its initial proposed implementation period due to startup and fieldwork taking longer than expected and due to various delays imposed by the forest service. II- Objectif du projet Indicateur Situation actuelle Objectif : L’objectif du projet est que le plan d’action pour la A series of workshops were held in Ambovombe (July conservation participative régionale est adopte par 2003) and Amboasary (Janvier 2004) with all the major les acteurs de conservation dans la région Androy conservation stakeholders in Androy (ANGAP, AFAFI, et qu’un méthode efficace sur le transfert de gestion ASOS, CIREEF, WWF, CGDIS, ALT ENERGIE, CNRE, des ressources naturelles utilisant une CI, TCT, CRD, PACT, KIOMBA, Local district authorities).
    [Show full text]
  • New Minerals Approved in 1998 by The
    247 The Canadian Mineralogist Vol. 37, pp. 247-252 (1999) NEW MINERALSAPPROVED IN 1998 BY THE COMMISSIONON NEW MINERALS AND MINERALNAMES. INTERNATIONAL MINERALOGICAL ASSOCIATION JOEL D. GRICE* CanadianMuseum of Nttture,P.O. Box 3443A,Station "D", Ottawa,Ontario KIP 6P4 GIOVANNI FERRARISX* Dipanimentodi ScienzeMineralogiche e Petrologiche,Universitd di Torino,Via ValpergaCaluso 35, I-10125Torino, Italy The information given here is provided by the Commission on New Minerals and Mineral Names (CNMMN), Intemational Mineralogical Association (IMA), for comparative purposesand as a service to mineralogists work- ing on new species.Each mineral is described in the following format: IMA Number Chemical Formula (any relationship to other minerals; structure analysis) Crystal system, spacegroup unit-cell parameters Color; luster; diaphaneity Optical properties Strongestlines in the X-ray powder-diffraction pattern td in A(I)l The namesof these approved speciesare consideredconfidential information until the authors have published their descriptions or releasedinformation themselves.No other information will be releasedby the Commission. 1998Pnoposers IMA No. 98-002 Ca:Ge(OH)6(SO+XCO:).12HzO A memberof IMA No. 98-001 the ettringitegroup; Cu3(AsOa)2.4H2O New structure-type structure OrthorhombiciPnma Hexagonal:P63/m a 5.6906.b t7.06I.c 9.82 A, a 11.056,c 10.629A Bottle green;vitreous; transparent White; vitreous;transparent Biaxial(-), u 1.745,B 1.755,1 1.760,2V(meas)11", Uniaxial(-), to 1.509,e 1.479 2V (calc)70" 8.52(100),3.721(60), 3.221(90), 9.57 (vs), 5. 5 3 (s), 3. 8 3 (s), 3. 56(ms), 3.44(m), 2.7 4(ms), 3.ro2(40), 2.8 r7 (3 5), 2.79 s (3 s), 2.3s0(25) 2.53(m) \ * Chairman, CNMMN.
    [Show full text]
  • Madagascar Food Security Project
    Final Evaluation report: Madagascar Food Security Project September 2017 Author: Antilahy Herimpitia Estelle Rolande (Consultant) Acknowledgements The Malagasy Red Cross and the International Federation of the Red Cross and Red Crescent Societies (IFRC) would like to express their gratitude to all those who participated in the evaluation mission of the FIHAVOTSE Project in Antananarivo, Amboasary Atsimo and Taolagnaro, from 9 to 27 July 2017. The evaluation team comprised of Ms. Herimpitia Estelle Rolande Antilahy (the National Consultant), Messrs. Sammy Fwanga and Geofrey Odera working for IFRC Nairobi, Kenya as the Monitoring & Evaluation Officer and the Emergency Planning and Reporting Officer respectively, and Mr. Emmanuel Ntakirutimana, the Monitoring & Evaluation Officer at the Rwandan Red Cross Society (RRCS). Special thanks to the project team who provided valuation information, and to the communities supported by the project with who the evaluation team spent time talking through the project interventions. Cover photo: Description of photo © XXX XXX 2 Acronyms AINA Action Intégrée en Nutrition et Sécurité Alimentaire (Integrated Action in Nutrition and Food Security - Programme funded by the European Union in South and South-East Madagascar) ASARA Amélioration de la Sécurité Alimentaire et du Revenu Agricole (Improved Food Security and Agricultural Revenue- Programme funded by the European Union in South and South-East Madagascar) AtC Accountability to Communities AUE Association des usagers de l’eau (Water Users’ Association)
    [Show full text]
  • Office of the Resident Coordinator Madagascar • Dahalo1 Attack Displaces People in the South Situation Update
    United Nations Nations Unies Office of the Resident Coordinator Madagascar • Dahalo 1 Attack Displaces People in the South Situation Update - 15 June 2012 This update is produced by the Resident Coordinator’s Office in collaboration with humanitarian partners. I. HIGHLIGHTS/KEY PRIOR ITIES • On 09 June 2012, heavily armed and well organized groups of dahalo (operating mostly in rural areas of Madagascar) carried out violent attacks on Ilambohazo village in the extreme southeast region of Anosy. • The attack left 6 people dead, all members of security forces (5 military personnel and 1 gendarme ). Another 7 agents were wounded and 4 are still missing. • After the attack, the dahalo threatened to attack six villages of Anosy Region in the following days which led to a population’s displacement towards Taolagnaro town. • Various local sources put the number of displaced people from the communes at risk at around 1,800 persons. Local authorities talked about some hundreds of people have temporarily settled in a piece of land in the town centre of Taolagnaro. • On 13 June , local authorities met to discuss the support they would provide to the IDPs and any other vulnerable families. • On 14 June, the Prime Minister, with the Minister of Defence, the Minister Internal Security and the Secretary of State for Gendarmerie and parliamentarians from the areas concerned, left the country’s capital city, Antananarivo, for Taolagnaro, to assess the security and humanitarian situation. • UN joint mission, chaired by the UNRC a.i. and composed of OCHA/RCO, WFP and UNICEF, also joined the Government mission to assess the humanitarian situation and prepare rapid needs assessment if necessary.
    [Show full text]
  • The Rutile Deposits of the Eastern United States
    THE RUTILE DEPOSITS OF THE EASTERN UNITED STATES. By THOMAS L. WATSON. INTRODUCTION. The titanium-bearing minerals comprise more than 60 distinct species, grouped under a variety of mineral and chemical forms, chiefly as oxides, titanates, titano-silicates, silicates, columbates, and iantalates. These minerals are widely distributed in a variety of associations and in such quantity as to make titanium a relatively abundant element. Clarke* estimates the. amount of titanium in the solid crust of the earth to be 0.44 per cent, equivalent in oxide to 0.73 per cent, the element thus standing in the ninth place in the scale of abundance, next to potassium. Most of the titanium-bearing minerals, however, are rare and are only of scientific interest. The largest concentrations of the element are as oxide (rutile), as iron titanate (ilmenite), and in iron ferrate (magnetite) as intergrown ilmenite. Of these three forms the prin­ cipal source of the element at present is rutile. The known workable deposits of rutile, however, are extremely few and widely sepa­ rated, and as the demand for titanium has greatly increased in the last few years it has been necessary for some uses to turn to ilmenite or highly titaniferous magnetites. This paper briefly summarizes present knowledge of the geology of the rutile deposits in the eastern United States and for the sake of comparison discusses several foreign deposits, each of which has produced some rutile. Of the known deposits in the United, States only those in Virginia are of commercial importance. These have been made the subject of a special report 2 by the Virginia Geological Survey, which was preceded by a preliminary paper on the rutile deposits of Amherst and Nelson counties.3 1 Clarke, F.
    [Show full text]
  • Kornerupine (Mg, Fe , Al, ☐)10(Si, Al, B)5O21(OH, F)
    2+ Kornerupine (Mg, Fe , Al, ☐)10(Si, Al, B)5O21(OH, F) Crystal Data: Orthorhombic. Point Group: 2/m 2/m 2/m. Crystals prismatic, to over 20 cm, showing principally {110}, {100}, and {010}, rarely terminated; as radiating aggregates. Physical Properties: Cleavage: Good on {110}. Hardness = 6-7 D(meas.) = 3.29-3.35 D(calc.) = 3.288 Optical Properties: Transparent to translucent and opaque. Color: Colorless, white, blue, green, dark green, greenish yellow, yellow-brown, black. Luster: Vitreous. Optical Class: Biaxial (-); may be pseudouniaxial (-). α = 1.660-1.671 β = 1.673-1.683 γ = 1.674-1.684 2V(meas.) = 3°-48° Pleochroism: X = colorless to green; Y = colorless, pale brownish yellow, pale yellowish green; Z = pale brownish green, green, light amber. Orientation: X = c; Y = a; Z = b. Dispersion: r < v or r > v. Cell Data: Space Group: Cmcm. a = 16.041(3) b = 13.746(2) c = 6.715(2) Z = 4 X-ray Powder Pattern: Mautia Hill, Tanzania. 2.639 (100), 3.03 (80), 3.37 (60), 2.118 (60), 1.503 (40), 2.096 (30), 1.685 (30) Chemistry: (1) (1) SiO2 29.80 MgO 18.96 TiO2 0.06 CaO 0.07 B2O3 1.44 Li2O 0.08 Al2O3 45.85 Na2O 0.04 FeO 1.60 F 0.01 MnO 0.05 H2O [1.21] Total [99.17] (1) Fiskenæsset, Greenland; by electron microprobe, Li, B, F by ion microprobe, H2O calculated from stoichiometry; corresponding to (Mg3.48Fe0.16Li0.04Ca0.01Na0.01Al5.64Ti0.01)Σ=9.35(Si3.67Al1.02 B0.31)Σ=5.00O21[(OH)0.99F0.01]Σ=1.00.
    [Show full text]
  • Khmaralite, a New Beryllium-Bearing Mineral Related to Sapphirine: a Superstructure Resulting from Partial Ordering of Be, Al, and Si on Tetrahedral Sites
    American Mineralogist, Volume 84, pages 1650–1660, 1999 Khmaralite, a new beryllium-bearing mineral related to sapphirine: A superstructure resulting from partial ordering of Be, Al, and Si on tetrahedral sites JACQUES BARBIER,1,* EDWARD S. GREW,2 PAULUS B. MOORE,3 AND SHU-CHUN SU4 1Department of Chemistry, McMaster University, Hamilton, Ontario, L8S 4M1 Canada 2Department of Geological Sciences, University of Maine 5790 Bryand Center Orono, Maine 04469, U.S.A. 3P.O. Box 703, Warwick, New York,10990, U.S.A. 4Hercules Research Center, 500 Hercules Road, Wilmington, Delaware 19808, U.S.A. ABSTRACT 3+ 2+ Khmaralite, Ca0.04Mg5.46Fe 0.12Fe 1.87Al14.26Be1.43B0.02Si4.80O40, is a new mineral closely related to sapphirine from Khmara Bay, Enderby Land, Antarctica. It occurs in a pegmatite metamorphosed at T ≥ 820 °C, P ≥ 10 kbar. The minerals surinamite, musgravite, and sillimanite associated with khmaralite at Casey Bay saturate it in BeO, and thus its BeO content could be close to the maximum possible. Optically, khmaralite is biaxial (–); at λ = 589 nm, α = 1.725(2), β = 1.740(2), γ = 1.741(2), 2Vmeas = 34.4 (1.8)°, v > r strong, and β b. The weak superstructure reported using electron diffraction has been confirmed by single-crystal X-ray diffraction. The superstructure corresponds to a doubling of the a axis in monoclinic sapphirine-2M (P21/c setting) with the following unit-cell parameters: a = 3 19.800(1), b = 14.371(1), c = 11.254(1) Å, β = 125.53(1)°, Z = 4, Dcalc = 3.61 g/cm .
    [Show full text]
  • The Journal of R
    The Journal of r Volumemmoie 28 Noemmoi. emmoi2 Apriol 200 2 o Notes from the Laboratory Chocolate- brown Opal Inclutsfbns in Gemstones Natural Amethyst hi1 (iemmoiotiuMl Asstvi.it inn .nij C iem Tcstiiv* I .ahoivitoi'v oi Crrot Britain Gemmological Association and Gem Testing Laboratory of Great Britain 27 Greville Street, London ECIN 8TN Tel: 020 7404 3334 Fax: 020 7404 8843 e-mail: [email protected] Website: www.gagtl.ac.uk President: Professor AT. Collins Vice-Presidents: N. W. Deeks, AE. Farn, RA Howie, D.G. Kent, RK. Mitchell Honorary Fellows: Chen Zhonghui, RA Howie, RT. Liddicoat [nr, K. Nassau Honorary Life Members: H. Bank, D.J. Callaghan, E.A [obbins, H. Tillander Council of Management: T.J. Davidson, RR Harding, 1. Mercer, J. Monnickendam, M.I. O'Donoghue, E. Stern, 1. Thomson, v.P. Watson Members' Council: AJ. Allnutt, S. Burgoyne, P. Dwyer-Hickey, S.A. Everitt, J. Greatwood, B. Jackson, L. Music, J.B. Nelson, P.G. Read, P.J. Wates, C.H. Winter Branch Chairmen: Midlands - G.M. Green, North West - D. M. Brady, Scottish - B. Jackson, South West - RM. Slater Examiners: AJ. Allnutt, M.Sc., PhD., FGA, L. Bartlett, B.5c., M.Phil., FGA, DGA, S. Coelho, B.5c., FGA, DGA, Prof. AT. Collins, B.Sc., Ph.D, A.G. Good, FGA, DGA, I. Greatwood, FGA, G.M. Howe, FGA, DGA, S. Hue Williams MA, FGA, DGA, B. Jackson, FGA, DGA, G.B. Jones, B.5c., Ph.D., FGA, Li Li Ping, FGA, DGA, M. Newton, B.Sc.,D.Phil., c.I.E. Oldershaw, B.Sc.
    [Show full text]
  • List of Abbreviations
    List of Abbreviations Ab albite Cbz chabazite Fa fayalite Acm acmite Cc chalcocite Fac ferroactinolite Act actinolite Ccl chrysocolla Fcp ferrocarpholite Adr andradite Ccn cancrinite Fed ferroedenite Agt aegirine-augite Ccp chalcopyrite Flt fluorite Ak akermanite Cel celadonite Fo forsterite Alm almandine Cen clinoenstatite Fpa ferropargasite Aln allanite Cfs clinoferrosilite Fs ferrosilite ( ortho) Als aluminosilicate Chl chlorite Fst fassite Am amphibole Chn chondrodite Fts ferrotscher- An anorthite Chr chromite makite And andalusite Chu clinohumite Gbs gibbsite Anh anhydrite Cld chloritoid Ged gedrite Ank ankerite Cls celestite Gh gehlenite Anl analcite Cp carpholite Gln glaucophane Ann annite Cpx Ca clinopyroxene Glt glauconite Ant anatase Crd cordierite Gn galena Ap apatite ern carnegieite Gp gypsum Apo apophyllite Crn corundum Gr graphite Apy arsenopyrite Crs cristroballite Grs grossular Arf arfvedsonite Cs coesite Grt garnet Arg aragonite Cst cassiterite Gru grunerite Atg antigorite Ctl chrysotile Gt goethite Ath anthophyllite Cum cummingtonite Hbl hornblende Aug augite Cv covellite He hercynite Ax axinite Czo clinozoisite Hd hedenbergite Bhm boehmite Dg diginite Hem hematite Bn bornite Di diopside Hl halite Brc brucite Dia diamond Hs hastingsite Brk brookite Dol dolomite Hu humite Brl beryl Drv dravite Hul heulandite Brt barite Dsp diaspore Hyn haiiyne Bst bustamite Eck eckermannite Ill illite Bt biotite Ed edenite Ilm ilmenite Cal calcite Elb elbaite Jd jadeite Cam Ca clinoamphi- En enstatite ( ortho) Jh johannsenite bole Ep epidote
    [Show full text]
  • The Crystal Structure of Aenigmatite E
    THE AMERICAN MINERALOGIST, VOL. 56, MARCH-APRIL, 1971 THE CRYSTAL STRUCTURE OF AENIGMATITE E. CANNILLO AND F. MAZZI, Centro di studio del C.N.R. per la cristal- lografia struturale, Istituto di Mineralogia dell' Universita di Pavia, Italy. AND J. H. FANG, PAUL D. ROBINSON, AND Y. OHYA, Department of Geology, Southern Illinois University, Carbondale, Illinois, U.S.A. ABSTRACT Aenigmatite, Na2Fe.TiSi602Q, is triclinic PI, with a= 10.406(13), b = 10.813(14), c=8.926(6) A, <>= 104° 56'(9), ~=96°52'(11), 1'= 125°19'(6), and Z = 2. The structure was solved, independently and simultaneously, by Patterson syntheses and by the symbolic addition procedure. Three-dimensional refinement with 921 "observed" reflections (photo- graphic data) from a Naujakasik, Greenland, crystal gave RhkZ=0.075 and with 1501 "observed" reflections (counter data) from a Kola, Greenland crystal gave Rhkl=O.072. A distinct pseudo-monoclinic symmetry, based on a cell with parameters: 11m= 12.120, b1O=2X14.815, c1O=1O.406 A, <>10=90°4', ~1O=127°9', 1'10=89°44' (matrix of transforma- tion [011jI22/100j), Z = 8, emphasizes the similarity of its crystal structure with that of sapphirine [(Mg, Alh02(Si, Al)6018, a=11.266, b=14.401, c=9.929 A, ~=125 °46', Z=4, space group P2i!a]. The crystal structure consists of two sets of polyhedral layers parallel to the pseudo- monoclinic (100) plane which alternate along the x*-direction. The first layer is formed by Fe-octahedra, Ti-octahedra and distorted Na-square antiprisms and the second by [Si601s]" chains connected by Fe-octahedra.
    [Show full text]
  • Exploring Ecosystem Valuation to Move Towards Net Positive Impact on Biodiversity in the Mining Sector
    Exploring ecosystem valuation to move towards net positive impact on biodiversity in the mining sector Nathalie Olsen, Joshua Bishop and Stuart Anstee IUCN and Rio Tinto Technical Series No.1 Exploring ecosystem valuation to move towards net positive impact on biodiversity in the mining sector Nathalie Olsen, Joshua Bishop and Stuart Anstee IUCN and Rio Tinto Technical Series No.1 ISBN: 978-2-8317-1379-3 Cover photo: © Ravoahangy Andriamandranto Layout by: The designation of geographical entities in this book, and the presentation of the millerdesign.co.uk material, do not imply the expression of any opinion whatsoever on the part of IUCN or Rio Tinto concerning the legal status of any country, territory, or area, or Printed by: of its authorities, or concerning the delimitation of its frontiers or boundaries. SRO-Kundig SA The views expressed in this publication do not necessarily reflect those of IUCN Available from: or Rio Tinto. IUCN (International Union for Published by: IUCN, Gland, Switzerland and Rio Tinto, London, UK Conservation of Nature) Copyright: © 2011 International Union for Conservation of Nature and Natural Publications Services Resources Rue Mauverney 28 1196 Gland Reproduction of this publication for educational or other non-commercial Switzerland purposes is authorized without prior written permission from the copyright holder provided the source is fully acknowledged. Tel +41 22 999 0000 Fax +41 22 999 0020 Reproduction of this publication for resale or other commercial purposes is [email protected] prohibited without prior written permission of the copyright holder. www.iucn.org/publications Citation: Olsen, Nathalie, Bishop, Joshua and Anstee, Stuart (2011).
    [Show full text]
  • Locality of the Geological Survey Area
    裏表紙 Locality of the Geological survey area Photo; landscape in the survey area Eastern K58 area East of J59 area K59 area Contents Chapter 1 Introduction ..........................................................................................................1 1.1 Background of the Project...........................................................................................1 1.2 Objectives of the Project .............................................................................................1 1.3 Survey area of the Project...........................................................................................2 1.4 Tasks of the Project.....................................................................................................3 1.5 Schedule of the Project ...............................................................................................4 1.6 Framework of implementation of the Project ...............................................................5 1.6.1 Structure of JICA Project Team.............................................................................5 1.6.2 Counterpart Organization .....................................................................................7 1.7 Works in Madagascar..................................................................................................9 1.7.1 Outline ..................................................................................................................9 1.7.2 Workshop ...........................................................................................................12
    [Show full text]