DOCSLIB.ORG

The Crystal Structure of Viitaniemiite

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Crystal Structure of Viitaniemiite American Mineralogist, Volume 69, pages 961-966, 1984 The crystal structure of viitaniemiite AenNE PeruNBN The University of Helsinki Department of Inorganic Chemistry Vuorikatu 20, SF-00100Helsinki 10, Finland eNo Sr,ppo L Lenrr Geological Survey of Finland Kivimiehentie l, SF-02150ESPOO 15, Finland Abstract The crystal structureof viitaniemiiteNa(Ca,Mn)AIPO4F2OH a : 5.457(2),b -- 7.151(2), c: 6.336(2)A,B: 109.36(3)"V :251.68A3, Z: 2, spacegroup P2/m, hasbeen solved by Pattersonand Fourier methodsand refinedby the least-squaresmethod to an R index of 0.037for 728observed (>2o) reflections.The structurecontains two setsof infinite chains parallel to the b-axis, one composedof A|O2(OH)2F2octahedra sharing opposite OH cornersand the other of (Ca,Mn)O+Fzoctahedra sharing opposite O-O edges.These chains alternatelaterally sharingF cornersto form a set of parallelsheets held togetherby POa tetrahedraand NaOaFagable disphenoids. The sheet structure of viitaniemiitecontaining octahedrally coordinated atoms in two separatepositions resemblesthat of montebrasiteand eosphorite.These three related phosphateminerals are associatedwith each other in the type locality of viitaniemiite, Viitaniemipegmatite, Orivesi, southernFinland, where they crystallizedduring hydrother- mal replacementprocesses caused by residualfluids of the pegmatitemelt. Introduction encounteredas very smallcrystals in vesiclesofsilicocar- bonatitetogether with cryolite, calcite,quartz, and welo- Viitaniemiite occurs as a rare hydrothermal mineral in ganite. Becausethe powder diffraction data of viitanie- the phosphate-richViitaniemi pegmatite,Orivesi, south- miite resemble those of an unnamed mineral from ern Finland.One of the authors(SIL) hasdescribed it asa Greifenstein,Sachsen, given on JCPDScard l3-0587,the new mineralin a study on the mineralogyand petrology of presentauthors studied several museum specimens taken the graniticpegmatities of the Eriijiirvi area(Lahti, l98l). from this locality and identified viitaniemiite from the The mineralwas encounteredas an inclusionin eosphor- sampleslabeled as lacroixite(cf. Mrose, l97l). According ite aggregateand is associatedwith morinite, another to the descriptinsby Slavik(1914, l9l5), lacroixite(and aluminum-bearingphosphate mineral. Structureanalysis therefore also viitaniemiite) occurs there in druses of confirmedthe ideal formula Na(Ca,Mn)AIPO4F2OHwith lithiogranitetogether with jeZekite(sodian morinite), apa- Z :2, althottghwet chemicalanalysis indicates that some tite, childrenite (Fe end member of the isomorphous of the fluorine may be replaced by OH groups. The serieschildrenite-eosphorite), roscherite, and tourmaline. crystal data measuredduring the structure analysisare Preliminary microanalyzerdeterminations showed that given in Table 1. The X-ray powder data, the optical Greifensteinviitaniemiite is rich in calcium and contaiirs properties,the chemicaldata, and the mineralogicalde- only a few percent of manganese;the fluorine content, scriptionof the mineral have beengiven by Lahti (1981) however,is equalto that of the Finnishviitaniemiite. Due andare not reproducedhere. A preliminarydescription of to its different chemical composition, the-Greifenstein the structurehas been given by Lahti and Pajunen(1982). viitaniemiitehas a largerunit cell (a -- 5.484, b = 7.184, To date viitaniemiitehas been identified positively in only c : 6.85A, F : 109.00',v = 254.8443;based on the three localities:at Viitaniemi. in museum specimens precessionfilms from sampleno. 86746in Harvard Min- collectedfrom drusesof granitein Greifenstein,Sachsen eralogicalMuseum). Detailed studies on the Greifenstein (East Germany),and from Franconquarry, northeastern viitaniemiiteand lacroixiteare in progress,because some Montreal, where its occurrencehas been confirmed by of the data cited for lacroixite obviously derive from Ramik et al. (1983). In this quarry viitaniemiite was viitaniemiite. 0003-004x/84/09I 0-096 l $02.00 961 962 PAJUNEN AND LAHTI: STRUCTURE OF VIITANIEMIITE Table l. Crystal data for viitaniemiite ed in the refinement with a fixed isotropic temperature factor (I : 0.0642. a = 5,45-ll2\A V = zSt.OAA3 The final refinement included positional parameters, b = 7.1.5I(2)A anisotropic thermal parameters, and occupancy factors = e 6.836(2) A D(calc.) = 2.242 S/q3 for calcium and manganese.The initial values for the B = 109.36(3)o ,(ms) = 3.245 g/m3 occupancyfactors were obtained from chemical analysis. Space gnp P2a,/n u(I4o(e) = 2.42 q-L The occupancy factors convergedto 0.592(5)for calcium (id@l) (Ca,th)ALPO4F2OH Fomla Na and 0.401(4)for manganese.Final R was 0.037, R* : 0.M3 and S = (IwAF2lm-111rrz: 4.12. The difference Experimental map had its largest electron density 0.61 eA-3 in the vicinity of the (Ca,Mn) atom. The calculations were For the structure analysis a transparent crystal plate of performedon a Univac I108 computerusing programs of viitaniemiitemeasuring about x x 0.1 0.2 0.3 mm was removed the xnay76 system (Stewart, 1976). The final atomic from the type material. Roundish crystals suitable for study are positions and thermal parameters are listed in Table 2. difficult to obtain, because the mineral forms thin, sometimes The interatomic radial, crystal plates (0.02-0.2 mm thick) flattened parallel to the distancesand bond anglesare reported in (l0T) plane. Table 3. Table 4, giving observedand calculatedstructure Single crystal X-ray precession photographs of this crystal factors, is on deposit at the Business Office of the l exhibit monoclinicsymmetry with systematicabsences 0k{, k: Mineralogical Society of America. 2n l- I consistentwith the spacegroups PTlm andP2,. The unit cell dimensions(298 K) given in Table I were obtainedby least- Description of the structure squaresrefinement of angular settingsof 20 reflections centered A stereoscopicview of the structure is presentedin on a Nicolet P3 automatic four-circle diffractometer -using Figure l. Al and (Ca,Mn) are in the centersof symmetry, graphite monochromatedMoKo radiation (I = 0.71074). A phosphorusand two of the oxygen atoms of the phos- uniqueset of intensitieswas measuredusing the r+scanmethod phate plane. with variablescan speed. Of the 788 reflectionswith 3. < 20 < ion are situated on the mirror The sodium 50",728were regardedas observed,their intensitybeing larger and hydroxyl ions are also on the mirror plane. Fluorine than 2.0 times the estimatedstandard deviation. Three standard and one oxygen of the phosphate ion are in general reflections measured for every 50 reflections showed no positions. systematic variation. The intensity data were corrected for Aluminum is surroundedby two oxygens,two hydrox- Lorentz and polarization efects and an empirical absorption yls and two fluorines in octahedral arrangement. The correction basedon the (ffscanmethod was applied (North et al., A1O2(OH)2F2octahedra form chains parallel to the b-axis l96E),with the coemcientranging from 0.707to 1.0. by sharing opposite OH- corners. In this 7A corner- sharing OH-AI-OH-AI chain (Moore, 1980) the OH Structure determination bridges are in trans configuration. (Ca,Mn) is surrounded The spacegroup, assumedto be PZ/m on the basisof by four oxygens and two fluorines in distorted octahedral diffraction intensity statistics, was later confirmed by the arrangement.The octahedra shareopposite O-O edgesto structuresolution. The symmetryin the spacegroup P2rl form a setofchains parallelto the b-axis.The sharededge m requiresthat most of the atomsbe in specialpositions. is considerablyshorter than the others, suggestingrepul- The structure was solved by Pattersonand Fourier meth- sion between neighboring (Ca,Mn) cations. The two ods. The Pattersonsynthesis showed that most of the chains alternate by sharing F corners to form a set of -r9.25. atomsare situatedat y : A solutionwas found for parallel sheets. Adjacent sheets are held together by Al and (Ca,Mn)in the centersof symmetry,for F and one phosphate ions. The phosphate ion is a nearly ideal O in general positions and for other atoms on the mirror tetrahedronwith O-P-O anglesin the range 108.3-112.2'. plane. Additional linkagebetween the sheetsis provided by the The atomic scattering factors used were those of Cro- NaOaFapolyhedron (Fig. 2). Five Na-O and Na-F dis- mer and Mann (1968)for non-hydrogenatoms with anom- tancesare between2.3-2.54, defininga distortedsquare alous dispersion coefficients from the International Ta- pyramid, but three additional distancesof 2.8A are in- bles for X-ray Crystallography (Ibers and Hamilton, cluded,resulting in a polyhedronwith coordinationnum- 1974), and, of Stewart et al (1965) for hydrogen. The ber eight. The next larger distancesare >3.14. This structure was refined by the full-matrix least-squares polyhedron, gable disphenoid, has been discussedin - rnethod.The function minimizedwas lwllF.l l,f'"||'zwith detail by Moore (1981).Previously it hasonly beenfound : unit weights.R 0.071was obtainedby refinementwith in wyllieite (Moore and Molin-Case, 1974)and fillowite isotropic temperature factors for non-hydrogen atoms. (Araki and Moore. l98l). The temperaturefactors were converted to anisotropic in the form given in Table 2; refinementreduced R to 0.057. ' To obtain a copy of Table 4, order Document Am-84-251 A diference map calculated at this stagerevealed a peak from the Mineralogical Society of America, Business Office, on the mirror plane lA from O(4). This peak was assumed 2000Florida Avenue, N. W., Washington,D. C. 20009.Please to be the hydrogenatom. The hydrogenatom was
Load more

Recommended publications
  • Kosnarite Kzr2(PO4)3 C 2001-2005 Mineral Data Publishing, Version 1
    Kosnarite KZr2(PO4)3 c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Hexagonal, pseudocubic. Point Group: 32/m. As rhombohedral pseudocubic crystals, to 0.9 mm, with {1012} and tiny {0001}. Physical Properties: Cleavage: Perfect on {1012}. Fracture: Conchoidal. Tenacity: Brittle. Hardness = 4.5 D(meas.) = 3.194(2) D(calc.) = 3.206 Optical Properties: Transparent to translucent. Color: Pale blue to blue-green, bluish gray, nearly colorless. Streak: White. Luster: Vitreous. Optical Class: Uniaxial (+). ω = 1.656(2) = 1.682(2) Cell Data: Space Group: R3c. a = 8.687(2) c = 23.877(7) Z = 6 X-ray Powder Pattern: Mt. Mica, Maine, USA. 4.329 (100), 3.806 (90), 2.928 (90), 6.41 (50), 4.679 (50), 2.502 (50), 1.903 (45) Chemistry: (1) (2) (3) P2O5 43.3 42.2 42.04 ZrO2 44.5 47.9 48.66 HfO2 0.5 0.9 FeO 0.2 < 0.1 MnO 1.0 < 0.1 Na2O 1.4 < 0.1 K2O 8.7 9.25 9.30 Rb2O 0.25 0.2 F 0.20 0.2 −O=F2 0.08 0.08 Total 99.97 100.57 100.00 (1) Mt. Mica, Maine, USA; by electron microprobe, total Fe as FeO, total Mn as MnO; corresponds to (K0.93Na0.08Rb0.01)Σ=1.02(Zr1.81Na0.15Mn0.07Fe0.01Hf0.01)Σ=2.05 [P1.02(O3.98F0.02)Σ=4.00]3. (2) Black Mountain, Maine, USA; by electron microprobe, total Fe as FeO, total Mn as MnO; corresponds to (K0.99Rb0.01)Σ=1.00(Zr1.96Hf0.02)Σ=1.98 [P1.00(O3.98F0.02)Σ=4.00]3.
    [Show full text]
  • The Secondary Phosphate Minerals from Conselheiro Pena Pegmatite District (Minas Gerais, Brazil): Substitutions of Triphylite and Montebrasite Scholz, R.; Chaves, M
    The secondary phosphate minerals from Conselheiro Pena Pegmatite District (Minas Gerais, Brazil): substitutions of triphylite and montebrasite Scholz, R.; Chaves, M. L. S. C.; Belotti, F. M.; Filho, M. Cândido; Filho, L. Autor(es): A. D. Menezes; Silveira, C. Publicado por: Imprensa da Universidade de Coimbra URL persistente: URI:http://hdl.handle.net/10316.2/31441 DOI: DOI:http://dx.doi.org/10.14195/978-989-26-0534-0_27 Accessed : 2-Oct-2021 20:21:49 A navegação consulta e descarregamento dos títulos inseridos nas Bibliotecas Digitais UC Digitalis, UC Pombalina e UC Impactum, pressupõem a aceitação plena e sem reservas dos Termos e Condições de Uso destas Bibliotecas Digitais, disponíveis em https://digitalis.uc.pt/pt-pt/termos. Conforme exposto nos referidos Termos e Condições de Uso, o descarregamento de títulos de acesso restrito requer uma licença válida de autorização devendo o utilizador aceder ao(s) documento(s) a partir de um endereço de IP da instituição detentora da supramencionada licença. Ao utilizador é apenas permitido o descarregamento para uso pessoal, pelo que o emprego do(s) título(s) descarregado(s) para outro fim, designadamente comercial, carece de autorização do respetivo autor ou editor da obra. Na medida em que todas as obras da UC Digitalis se encontram protegidas pelo Código do Direito de Autor e Direitos Conexos e demais legislação aplicável, toda a cópia, parcial ou total, deste documento, nos casos em que é legalmente admitida, deverá conter ou fazer-se acompanhar por este aviso. pombalina.uc.pt digitalis.uc.pt 9 789892 605111 Série Documentos A presente obra reúne um conjunto de contribuições apresentadas no I Congresso Imprensa da Universidade de Coimbra Internacional de Geociências na CPLP, que decorreu de 14 a 16 de maio de 2012 no Coimbra University Press Auditório da Reitoria da Universidade de Coimbra.
    [Show full text]
  • Mineral Collecting Sites in North Carolina by W
    .'.' .., Mineral Collecting Sites in North Carolina By W. F. Wilson and B. J. McKenzie RUTILE GUMMITE IN GARNET RUBY CORUNDUM GOLD TORBERNITE GARNET IN MICA ANATASE RUTILE AJTUNITE AND TORBERNITE THULITE AND PYRITE MONAZITE EMERALD CUPRITE SMOKY QUARTZ ZIRCON TORBERNITE ~/ UBRAR'l USE ONLV ,~O NOT REMOVE. fROM LIBRARY N. C. GEOLOGICAL SUHVEY Information Circular 24 Mineral Collecting Sites in North Carolina By W. F. Wilson and B. J. McKenzie Raleigh 1978 Second Printing 1980. Additional copies of this publication may be obtained from: North CarOlina Department of Natural Resources and Community Development Geological Survey Section P. O. Box 27687 ~ Raleigh. N. C. 27611 1823 --~- GEOLOGICAL SURVEY SECTION The Geological Survey Section shall, by law"...make such exami­ nation, survey, and mapping of the geology, mineralogy, and topo­ graphy of the state, including their industrial and economic utilization as it may consider necessary." In carrying out its duties under this law, the section promotes the wise conservation and use of mineral resources by industry, commerce, agriculture, and other governmental agencies for the general welfare of the citizens of North Carolina. The Section conducts a number of basic and applied research projects in environmental resource planning, mineral resource explora­ tion, mineral statistics, and systematic geologic mapping. Services constitute a major portion ofthe Sections's activities and include identi­ fying rock and mineral samples submitted by the citizens of the state and providing consulting services and specially prepared reports to other agencies that require geological information. The Geological Survey Section publishes results of research in a series of Bulletins, Economic Papers, Information Circulars, Educa­ tional Series, Geologic Maps, and Special Publications.
    [Show full text]
  • Roscherite-Group Minerals from Brazil
    ■ ■ Roscherite-Group Minerals yÜÉÅ UÜté|Ä Daniel Atencio* and José M.V. Coutinho Instituto de Geociências, Universidade de São Paulo, Rua do Lago, 562, 05508-080 – São Paulo, SP, Brazil. *e-mail: [email protected] Luiz A.D. Menezes Filho Rua Esmeralda, 534 – Prado, 30410-080 - Belo Horizonte, MG, Brazil. INTRODUCTION The three currently recognized members of the roscherite group are roscherite (Mn2+ analog), zanazziite (Mg analog), and greifensteinite (Fe2+ analog). These three species are monoclinic but triclinic variations have also been described (Fanfani et al. 1977, Leavens et al. 1990). Previously reported Brazilian occurrences of roscherite-group minerals include the Sapucaia mine, Lavra do Ênio, Alto Serra Branca, the Córrego Frio pegmatite, the Lavra da Ilha pegmatite, and the Pirineus mine. We report here the following three additional occurrences: the Pomarolli farm, Lavra do Telírio, and São Geraldo do Baixio. We also note the existence of a fourth member of the group, an as-yet undescribed monoclinic Fe3+-dominant species with higher refractive indices. The formulas are as follows, including a possible formula for the new species: Roscherite Ca2Mn5Be4(PO4)6(OH)4 • 6H2O Zanazziite Ca2Mg5Be4(PO4)6(OH)4 • 6H2O 2+ Greifensteinite Ca2Fe 5Be4(PO4)6(OH)4 • 6H2O 3+ 3+ Fe -dominant Ca2Fe 3.33Be4(PO4)6(OH)4 • 6H2O ■ 1 ■ Axis, Volume 1, Number 6 (2005) www.MineralogicalRecord.com ■ ■ THE OCCURRENCES Alto Serra Branca, Pedra Lavrada, Paraíba Unanalyzed “roscherite” was reported by Farias and Silva (1986) from the Alto Serra Branca granite pegmatite, 11 km southwest of Pedra Lavrada, Paraíba state, associated with several other phosphates including triphylite, lithiophilite, amblygonite, tavorite, zwieselite, rockbridgeite, huréaulite, phosphosiderite, variscite, cyrilovite and mitridatite.
    [Show full text]
  • A Specific Gravity Index for Minerats
    A SPECIFICGRAVITY INDEX FOR MINERATS c. A. MURSKyI ern R. M. THOMPSON, Un'fuersityof Bri.ti,sh Col,umb,in,Voncouver, Canad,a This work was undertaken in order to provide a practical, and as far as possible,a complete list of specific gravities of minerals. An accurate speciflc cravity determination can usually be made quickly and this information when combined with other physical properties commonly leads to rapid mineral identification. Early complete but now outdated specific gravity lists are those of Miers given in his mineralogy textbook (1902),and Spencer(M,i,n. Mag.,2!, pp. 382-865,I}ZZ). A more recent list by Hurlbut (Dana's Manuatr of M,i,neral,ogy,LgE2) is incomplete and others are limited to rock forming minerals,Trdger (Tabel,l,enntr-optischen Best'i,mmungd,er geste,i,nsb.ildend,en M,ineral,e, 1952) and Morey (Encycto- ped,iaof Cherni,cal,Technol,ogy, Vol. 12, 19b4). In his mineral identification tables, smith (rd,entifi,cati,onand. qual,itatioe cherai,cal,anal,ys'i,s of mineral,s,second edition, New york, 19bB) groups minerals on the basis of specificgravity but in each of the twelve groups the minerals are listed in order of decreasinghardness. The present work should not be regarded as an index of all known minerals as the specificgravities of many minerals are unknown or known only approximately and are omitted from the current list. The list, in order of increasing specific gravity, includes all minerals without regard to other physical properties or to chemical composition. The designation I or II after the name indicates that the mineral falls in the classesof minerals describedin Dana Systemof M'ineralogyEdition 7, volume I (Native elements, sulphides, oxides, etc.) or II (Halides, carbonates, etc.) (L944 and 1951).
    [Show full text]
  • Anatomía, Mineralogía Y Geoquímica Mineral Pegmatites from Barroso-Alv
    Cadernos Lab. Xeolóxico de Laxe Coruña. 2011. Vol. 36, pp. 177 - 206 ISSN: 0213-4497 Las pegmatitas de Barroso-Alvão, Norte de Portugal: anatomía, mineralogía y geoquímica mineral Pegmatites from Barroso-Alvão, Northern Portugal: anatomy, mineralogy and mineral geochemistry MARTINS, T.1 and LIMA, A.2 (1) Geology Centre-Porto University; Rua do Campo Alegre, 687; 4169-007 Porto, Portugal ([email protected]) (2) Department of Geosciences, Environment and Spatial Planning, Rua do Campo Alegre, 687; 4169- 007 Porto, Portugal ([email protected]) Recibido: 13/12/2010 Revisado: 5/02/2011 Aceptado: 20/02/2011 Abstract The Barroso-Alvão pegmatite field is located in the Variscan belt, in the western part of the Iberian Peninsula, Northern Portugal and it is recognised for its numerous and varied aplite- pegmatite intrusions. This is a rare-element aplite-pegmatite field with enrichment in Li, Sn, Nb>Ta, Rb, and P. Several hundreds of pegmatite bodies were identified and described in this field area intruding a variety of rock types including different metasedimentary, and granitic rocks. In this study we present the geology and mineralogy, and mineral geochemistry of different types of aplite-pegmatites bodies found at Barroso-Alvão. Their description was based on field observa- tion, mineralogy, emplacement of the bodies and geochemical data. There were identified five dif- ferent groups: intragranite pegmatites with major quartz, feldspar, muscovite, biotite, and minor tourmaline, beryl and garnet; barren pegmatites with quartz, feldspar, muscovite, and minor bi- otite, apatite, and beryl, among other accessories; spodumene pegmatites with spodumene, Nb-Ta minerals, and Mn-Fe-Li phosphates, along with other accessory mineral phases; petalite pegma- 178 Martins and Lima CAD.
    [Show full text]
  • REVISION 1 Mössbauer Spectroscopic Study of Natural Eosphorite
    1 1 REVISION 1 2 3 Mössbauer spectroscopic study of natural eosphorite, [(Mn, Fe)AlPO4(OH)2H2O] 4 Antoine Van Alboom1,2,Valdirene Gonzaga de Resende1, Geraldo Magela da Costa3 and Eddy 5 De Grave1* 6 7 1Department of Physics and Astronomy, University of Ghent, B-9000 Gent, Belgium 8 2Department of Industrial Technology and Construction, University of Ghent, B-9000 Gent, 9 Belgium 10 3Chemistry Department, Federal University of Ouro Preto, 35400-000, Ouro Preto (MG), 11 Brazil 12 13 14 * E-mail: [email protected] 15 16 17 18 2 19 Abstract 57 2+ 20 A Fe Mössbauer spectroscopic study of natural eosphorite, (Mn, Fe )AlPO4(OH)2H2O, is 21 reported. The Mössbauer spectra were collected at temperatures between 295 K and 4.2 K. At 22 temperatures exceeding 30 K, the Mössbauer spectra consist of a somewhat broadened 23 quadrupole doublet with a splitting of 1.73 mm/s at 295 K. From the spectrum recorded at 250 24 K in an external magnetic field of 60 kOe, it is derived that the sign of the principal 25 component of the electric field gradient (EFG) is negative and that the EFG’s asymmetry 26 parameter is large (~0.5). From these findings, it is concluded that the octahedral coordination 27 of the ferrous cations exhibits in first order a trigonal compression with a further lowering 28 from axial symmetry due to an additional distortion. The spectrum collected at 4.2 K shows 29 the existence of magnetic ordering. It was analysed in terms of the full hyperfine interaction 30 Hamiltonian, yielding a magnetic hyperfine field value of 146 kOe and EFG characteristics 31 that are fully in line with those obtained from the external-field spectrum.
    [Show full text]
  • Aluminium-Bearing Strunzite Derived from Jahnsite at the Hagendorf-Su¨D Pegmatite, Germany
    Mineralogical Magazine, October 2012, Vol. 76(5), pp. 1165–1174 Aluminium-bearing strunzite derived from jahnsite at the Hagendorf-Su¨d pegmatite, Germany 1, 1 2 3 I. E. GREY *, C. M. MACRAE ,E.KECK AND W. D. BIRCH 1 CSIRO Process Science and Engineering, Box 312 Clayton South, Victoria 3169, Australia 2 Algunderweg 3, D À 02694 Etzenricht, Germany 3 Geosciences, Museum Victoria, GPO Box 666, Melbourne, Victoria 3001, Australia [Received 15 May 2012; Accepted 23 July 2012; Associate Editor: Giancarlo Della Ventura] ABSTRACT 2+ 3+ Aluminium-bearing strunzite, [Mn0.65Fe0.26Zn0.08Mg0.01] [Fe1.50Al0.50] (PO4)2(OH)2·6H2O, occurs as fibrous aggregates in a crystallographically oriented association with jahnsite on altered zwieselite samples from the phosphate pegmatite at Hagendorf Su¨d, Bavaria, Germany. Synchrotron X-ray data were collected from a 3 mm diameter fibre and refined in space group P1¯ to R1 = 0.054 for 1484 observed reflections. The refinement confirmed the results of chemical analyses which showed that one quarter of the trivalent iron in the strunzite crystals is replaced by aluminium. The paragenesis revealed by scanning electron microscopy, in combination with chemical analyses and a crystal-chemical comparison of the strunzite and jahnsite structures, are consistent with strunzite being formed from jahnsite by selective leaching of (100) metalÀphosphate layers containing large divalent Ca and Mn atoms. KEYWORDS: Al-bearing strunzite, strunzite paragenesis, strunzite structure refinement, Hagendorf Su¨d secondary phosphates. Introduction The feldspar pegmatite at Hagendorf Su¨d, 2+ 3+ STRUNZITE, ideally Mn Fe2 (PO4)2(OH)2·6H2O, Bavaria, contains a large number of secondary is a relatively rare secondary phosphate mineral Al-phosphates including eosphorite, kingsmoun- found in altered granitic pegmatites (Moore, tite, paravauxite, fluellite, morinite, variscite, 1965; Viana and Prado, 2007; Dill et al., 2008).
    [Show full text]
  • Eosphorite Mn2+Al(PO4)(OH)2 •
    2+ Eosphorite Mn Al(PO4)(OH)2 • H2O c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Monoclinic, pseudo-orthorhombic. Point Group: 2/m; pseudo 2/m 2/m 2/m. Typically as crystals, short to long prismatic on [001], to 20 cm; in planar radial or spherical radiating groups, with wedge-shaped terminations; globular, rarely massive. Twinning: May show twinning on {100} and {001}, observed optically, to give pseudo-orthorhombic symmetry; perhaps due to oxidation. Physical Properties: Cleavage: {100}, poor. Fracture: Subconchoidal to uneven. Hardness = 5 D(meas.) = 3.06–3.08 D(calc.) = 3.04 Optical Properties: Transparent to translucent. Color: Pink to rose-red, commonly brown to black when oxidized. Streak: White. Luster: Vitreous to resinous. Optical Class: Biaxial (–). Pleochroism: X = yellow; Y = pink; Z = pale pink to colorless. Orientation: X = b; Y = a; Z = c; Y ∧ c =4◦–8◦ in optically twinned individuals. Dispersion: r< v,strong, for near end-member composition. α = 1.628–1.644 β = 1.648–1.673 γ = 1.657–1.679 2V(meas.) = 45◦–50◦ in optically twinned crystals. ◦ Cell Data: Space Group: P 21/m. a = 10.455(1) b = 13.501(2) c = 6.928(1) β =90.0 Z=8 X-ray Powder Pattern: Newry, Maine, USA. (ICDD 17-131). 2.826 (100), 2.422 (60b), 5.23 (50), 4.39 (50), 3.55 (50), 3.41 (50), 1.535 (50b) Chemistry: (1) (2) P2O5 29.89 31.00 Al2O3 22.37 22.27 FeO 1.38 MnO 29.94 30.99 H2O 15.34 15.74 insol.
    [Show full text]
  • The American Journal of Science
    THE AMERIOAN JOURNAL OF SOIENCE. EDITORS JAMES D. AND EDWARD S. DANA. J I ASSOCIATE EDITORS Pa0FE880BS JOSIAH P. COOKE, GEORGE L. GOODALE AND JOHN TROWBRIDGE, OF CAllBaIDGB. PKOFE880B8 H. A. NEWTON AND A. E. VERRILL, OF NEW HAVEN, PBOFE880B GEORGE F. BARKER, OF' PHILADBLPWA. 1 THIRD SBRIBS. VOL. XXXIX.--,-[WHOLE NUMBER, CXXXIX.] Nos. 229-234. JANUARY TO JUNE, 1890. WITH YUI PLATES. NEW HAVEN, CONN.: J. D. & E. S. DANA. 1890. Brush and J}ana-Kine1'al Locality at Branchville. 201 urnes, and enough water to increase the total volume to 100 cm', or a little more. A platinum spiral is introduced, a trap made of a straight two-bulb drying-tube cut off short is hun~ with the larger end downward in the neck of the flask, and the liquid is boiled until the level reaches the mark put upon the flask to indicate a volume of 35 cm'. Great care should be taken not to press the concentration beyond this point on ac- o count of the double danger of losing arsenious chloride and setting up reduction of the arseniate by the bromide. On the other hand, though 35 cm' is the ideal volume to be attained, failure to concentrate below 40 cm' introduces no appreciable error. The liquid remaining is cooled and nearly neutralized by sodium hydrate (ammonia is not equally good), neutraliza­ tion is completed by hydrogen potassium carbonate, an excess of 20 cm' of the saturated AolutlOn of the latter is added, and the arsenious oxide in solution is titrated by standard iodine in the presence of starch.
    [Show full text]
  • Sem–EDX, Raman and Infrared Spectroscopic Characterization Of
    Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 110 (2013) 7–13 Contents lists available at SciVerse ScienceDirect Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy journal homepage: www.elsevier.com/locate/saa SEM–EDX, Raman and infrared spectroscopic characterization of the phosphate 2+ 3+ mineral frondelite (Mn )(Fe )4(PO4)3(OH)5 ⇑ Ray L. Frost a, , Yunfei Xi a, Ricardo Scholz b, Fernanda M. Belotti c, Martina Beganovic b a School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia b Geology Department, School of Mines, Federal University of Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, MG 35400-00, Brazil c Federal University of Itajubá, Campus Itabira, Itabira, MG, Brazil highlights graphical abstract " We have analyzed a frondelite mineral sample from the Cigana mine, located in the municipality of Conselheiro Pena. " The chemical formula was determined as (Mn0.68, 3+ Fe0.32)(Fe )3,72(PO4)3.72(OH)4.99. " The structure of the mineral was assessed using vibrational spectroscopy. " Bands attributed to the stretching 3À and bending modes of PO4 and 3À HOPO3 units were identified. article info abstract Article history: We have analyzed a frondelite mineral sample from the Cigana mine, located in the municipality of Con- Received 3 July 2012 selheiro Pena, a well-known pegmatite in Brazil. In the Cigana pegmatite, secondary phosphates, namely Received in revised form 6 November 2012 eosphorite, fairfieldite, fluorapatite, frondelite, gormanite, hureaulite, lithiophilite, reddingite and vivia- Accepted 11 February 2013 nite are common minerals in miarolitic cavities and in massive blocks after triphylite.
    [Show full text]
  • REVISION 1 Magmatic Graphite Inclusions in Mn-Fe-Rich Fluorapatite
    1 REVISION 1 2 3 Magmatic graphite inclusions in Mn-Fe-rich fluorapatite of perphosphorus granites (the 4 Belvís pluton, Variscan Iberian Belt) 1 1, 2 3 5 Cecilia Pérez-Soba , Carlos Villaseca and Alfredo Fernández 6 1 7 Departamento de Petrología y Geoquímica, Facultad de Ciencias Geológicas, Universidad 8 Complutense de Madrid, c/ José Antonio Novais 12, 28040 Madrid, Spain 2 9 Instituto de Geociencias IGEO (UCM, CSIC), c/ José Antonio Novais 12, 28040 Madrid, 10 Spain 3 11 Centro Nacional de Microscopía. Universidad Complutense de Madrid, 28040 Madrid, 12 Spain 13 14 Abstract 15 Three Mn-Fe-rich fluorapatite types have been found in the highly evolved peraluminous and 16 perphosphorous granites of the Belvís pluton. One of these apatite types includes abundant 17 graphite microinclusions, suggestive of a magmatic origin for the graphite. The Belvís pluton is 18 a reversely zoned massif composed by four highly fractionated granite units, showing a varied 19 accessory phosphate phases: U-rich monazite, U-rich xenotime, U-rich fluorapatite and late 20 eosphorite-childrenite. The strong peraluminous character of the granites determines an earlier 21 monazite and xenotime crystallization, so the three types of fluorapatite records late stages of 22 phosphate crystallization. The earlier type 1 apatite is mostly euhedral, small and clear; type 2 23 apatite is dusty, large (< 2800 μm) and mostly anhedral, with strong interlobates interfaces with 24 the main granite minerals, more abundant in the less fractionated units and absent in the most 25 evolved unit; type 3 is subeuhedral to anhedral, shows feathery aggregate texture, and only 26 appears in the most evolved unit.
    [Show full text]