DOCSLIB.ORG

JENNITE, a NEW MINERAL Abcqnpbnrort, Department Oj

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

THE AMERICAN MINERALOGIST, VOL. 51, JANUARY FEBRUARY, 1966 JENNITE, A NEW MINERAL A. B. C.q.npBNrort,Department oJ Geology' Uni,tters'ity of Missouri,Columbia, Missowri; R. A. Cu.q'mons,J' A' Genl, K. Spnexu.q'NAND H. F. W. Tavron, Department of Chemistry, Ltniaersityof Aberdeen,Scotland,. Aesrnact of approrimate composition Jennite is a neu' mineraL from Crestmore, California, NazCaiSi;O:oHn.Itistriclinic,witho:10.56,b:725,c:108i A,a:99"42',8:97o40', y:110o04,, Z:1.It forms blade-shaped crystals I'ith length 6 and cleavage (001). The -74'; refractive indices are q:7.552, 9:1.564, t:l'571; 2V (calc.): aA(001):90', discovererof the mineral. INtnoouctroN The contact rocks at Crestmore, California were first describedb1' Eakle (1917). Man1, subsequentinvestigations on them have been re- ported; Murdoch (1961)has given a recent survey''Ihe object of the presentpaper is to describea nelv mineral found at this locality by Col- at the onel C. M. Jenni, who is now director of the geologicalmuseum university of \Iissouri. The chemicalcomposition, f-ray powder pattern, and other data for this mineral show that it is a new species,and the name jennite is proposedin honor of its discoverer. Occunnoxco open spacesin Jennite occurs as a late-stagemineral partially filling f ractured calcite-monticellite-hercyniteand vesuvianite-lvollastonite contact rock at Crestmore.The monticellite has been altered to serpen- tine plus calcitefor five or more centimeterson either sideof the fractures although the rvollastonitein the vesuvianite-wollastoniterock has been and is unaff".t"d. Jennite is alwal-s associatedwith 14 A tobermorite occasionallyfound with scawtiteand calcite.Scawtite and calciteare the earliestminerals in the fractures and may be encrustedby 14 A tober- morite, jennite or both. Scawtitecrvstals in jennite-bearingfractures are unaltered rn'hereasthe calcite is slightly etched and corroded. The jennite studied in the presentinvestigation formed part of a vein TENNITE, A NEW SILICATE 57 about 1 cm thick, having a central cavity. The vein consistedof several 1a1'ers,some of which were composedof calcite, and others of white, librous material. Representativefibers from each raver were examined by r-ray- rotation photographs.In some of the layers the jennite was intergrown with 14 A tobermorite, but in others it was free from other minerals.Some 200 mg were selectedfor use in the investisation. Prism o.A. Frc 1. Optic orientation for jennite: crystal viewed along a direction normal to the cleavase. Oprrcar PnopBnrrns Jennite forms small blade-shapedcrystals or fibrous aggregates.It is biaxialnegative, with a:1.552, B:1.564, 7:1.571, all +0.003; 2V (calc.):74'. Fig. 1 showsthe optic orientation.X is perpendicularto the cleavage,and Y makesan angleof 35-40' with the directionof eiongation of the blade. crystals lying on the cleavageshow inclined extinction; when the bladesare lying on edge,thev show parallel extinction. These resultsshow that the symmetrv is not higher than monoclinic;the r-ray evidence,described in the next section, indicates that the mineral is triclinic. 58 CARPENTER,CHALMT,RS, GARI), SPLAKMAN AND TAYLOR Uwrr CBrr, lNo X-R,q.v PowoBn D.qrA' The unit cell was determined from r-ray rotation' oscillation and Weissenbergphotographs about the direction of elongation,which will be called 6. It is triclinic. The parametersof the direct and reciprocal cells are siven below: Direct cell Reciprocalcell o 10.56A a* 0.10309A-1 b 72sA b* 0.15095A-t c 10814 c* 0.09597A-1 a 99"421 q* 76"M' p 97'40', B* 78"00' a tt0"04' r* 68"00' v 748.9A3 v* 0.001335A-3 The cleavageis (001). Reflectionshaving odd valttesof k are system- aticalh'weak: the pseudo cell obtained bv ignoring them is A-centered monoclinic,u'irh a q.q17,b 3.624,c 21.306A, B t0z'00' (door:20.858A). The o* and c* reciprocalaxes coincide in directionin the true and pseudo celis,and are normal to the direction of elongation.The triclinic 020 re- ciprocal lattice point coincideswith the 111 reciprocallattice point for the monoclinicpseudo ceil. If all three axesof the pseudocell are doubled, all reflectionscan be indexedon monoclinicaxes;however, the reciprocal lattice has monoclinic symmetry only as regalds reflections with fr even' It the doubled monoclinic axes are used, systematic absencesoccur among leflections with ft odd such that whenever hkl is ptesent, hhl is absent,and vice versa. No deviationsfrom 90" in the values of a and'y for this cell could be detected.These relationships, which are illustrated for the direct cell in Fig. 2, are similar to thosefound with nekoite (Gard and Taylor, 1956). X-ray powder data (Table 1) were obtained using 6-cm and 11.46-cm diameter cameras and rvith a diffractometer. Filtered copper radiation (\:1.542 A) *ur rLsedthroughout. Spacings longcr than 1.8A werein- dexed, chieflr. b1' direct comparison of 6 cm powder photographs with oscillation and rotation photographs taken on the same cameral due accountrvas taken of intensitiesas well as of spacings.In the caseof re- flectionsrvith fr odd, calculatedspacings are listed only for d>3.500 A; reflections of this t.vpe and shorter spacing were extremell' weak on single-crystalphotographs and undetectedon powder photographs' CnBurc.lr, AN,Llvsrs, DeNsrrv ANDAroMrc Carr, CoNrBNrs 'Ihe A chemicalanalvsis gave the resultsshown in Table 2, column 1. density, determinedb-v suspension, lvas 2.32 g/cc. A value was also cal- culated from the mean refractive index usir-rgthe Lorentz-Lotenz eqva' I]JNNITD, A NEW SILICATE 59 tion, assumingatomic r-efractionsCa: Na: 3.25, O: 3.65, H: Si:0 (Howison and Tavlor, 1956); this gave2.3I g/cc. The atomic cell con_ tents (Table 2, col.2) were calcuiatedfrom the chemicaianalysis assum- ing a density oI 2.32 g/cc and the cell vorume or 74g.9Ar obiaineclfrom the *-raf investigation.on the basisof the thermal decompositionstudy 1 o Jo" lbr I , I t I 6.:-:,- \q 6S' _:' \" 112cu (zt :oo 8) values of fr are ignored. describedlater, it was assumedthat all the 'rvaterwas combined.The formula approximatesto NazcaeSi5o36H22,withz:1 for the triclinic cell. TuBnlr,q,r D rcolrpo srrtor.r A thermal r,veightloss curve (Fig. 38, curve 1) was determined by heating a sample to constant weight at successivelyhigher temperatures in nitrogen. Periodsof a few days were neededat each temperature to reach constant weight, and the complete run took several weeks.The samplewas heatedin a platinum microboat which was placed in a silica tube furnace. The latter was filled with dry, COz-freeNz before each heating period. During heating, one end of the furnace was closedand. 60 CARPENTER, CHALMI'RS, GARD, SPLAK],TAN AND TAYLOR Taer.a 1. X-R,lv Pomnn Date lon JrNNtrr (CuKa Radiation, 1'542 A) Observed Calculated Indices spacrng hhl2 d (A) Iretl d (A) 10.5 001 t0 420 100 9 700 101 7 975 110 6.780 010 6 625 646 101 6 462 011 6 283 595 111 5 932 It I 5.463 5.20 002 5.210 011 5 .086 102 5 048 2r0 4 881 200 4 850 20I 1.795 rt1 4.79s m/b I \rto 4 71r 012 4 648 448 211. 4.489 2rl 4 -354 172 4 324 102 4 237 201 4 084 112 4 071 202 3.987 1),2 3 963 1il 3 921 012 3 703 212 T2o,lt| 3 570 103 3 510 347 003 3 473 02r,220 3 390 lo2o,2rr 3.29 ms/b l3oI 3.288 300 3 233 202 3 231 3. 19 721,122 3 213 203 3.151 022,22r 3.142 1s:strong, m:moderate(ly), w:weak, v:very, b:broad. The five stlongestspacings are in bold type. :Indicesrelatetothetricliniccellwitha10.56,bT25,clO8lA.aggo42',897040',,110"04'Allspacings longer than 3.500 A, and all spacings with even i indices and longer than I 800 A, are listed The matrix for transforming the indices to the large, monoclinic cell (a 19.83+,b 7.248, c 42.612A, B 102'00',) is Il21o/o1o /0141]. J]'NNITIJ, A NEW SILICATD Tl.nrr. l-(continued) Observed Calculated Indices spacrng I hhtz d r.\\ I.erl d (A) 103 3 074 304 302 3 046 021,222 2 966 2.92 {t21,s2o 2 926 [301 2 921 2.43 120,321 2 828 2i8 122,321 2 806 I22, 123 2 735 023,222 2 731 2.66 /:os 2 658 261 \ ro+ 2 658 004 2 605 20s 2 581 r21,,322 2 567 022,223 2-543 123,322 2.535 201 2 521 302 2.522 401 2 179 221, 420 2 410 2.43 400 2 .425 210 102 2 398 222,42L 2.397 10,1 2 394 220,42r 2.355 02!l,223 2 324 123,121 2.301 304 2 27s 401 2.261 122,323 2 254 223,422 2 245 121,323 2 221 403 2 216 22r,422 2.t77 023,224 2 162 303 2 154 105 2.t31 204 2 1r9 Joos 2 084 l2o5 2 078 402 2.O42 321,520 2.O40 224,423 2 035 322, 52r 2.032 401 r.994 Is01 1 983 1205,224 1.981 [320,s?1 1,974 222,+23 1.960 123,324 1.960 CARPENTER, CHALMERS, GARD, SPEAKMAN AND TAYLOR T.trr,B 1 (continued) Calculated Indices spacrng hkl2 d (A) d (A) 502 1.956 1 957 mw 105 1.956 323,522 1 951 1 946 MW t24,r25 1 951 500 1.940 r25,324 1 931 503 1.867 321,522 I 8.52 024,225 1.851 304 1.849 501 I .840 321,523 t.822 403 1.819 225,+21 | 817 241 1.812 1 683 mlv 7.637 1 610 1.58 vw/b t.52I L.486 t .455 | 413 1.393 I 365 I 331 r.312 r.266 r.2t1 1.177 1.173 1.155 t.r14 the other connected to two absorption tubes containing standard Ba(OH), solution.
Recommended publications
  • Phillipsite and Al-Tobermorite Mineral Cements Produced Through Low-Temperature Water-Rock Reactions in Roman Marine Concrete Sean R

    Phillipsite and Al-Tobermorite Mineral Cements Produced Through Low-Temperature Water-Rock Reactions in Roman Marine Concrete Sean R

    Western Washington University Western CEDAR Geology Faculty Publications Geology 2017 Phillipsite and Al-tobermorite Mineral Cements Produced through Low-Temperature Water-Rock Reactions in Roman Marine Concrete Sean R. Mulcahy Western Washington University, [email protected] Marie D. Jackson University of Utah, Salt Lake City Heng Chen Southeast University, Nanjing Yao Li Xi'an Jiaotong University, Xi'an Piergiulio Cappelletti Università degli Studi di Napoli Federico II, Naples See next page for additional authors Follow this and additional works at: https://cedar.wwu.edu/geology_facpubs Part of the Geology Commons Recommended Citation Mulcahy, Sean R.; Jackson, Marie D.; Chen, Heng; Li, Yao; Cappelletti, Piergiulio; and Wenk, Hans-Rudolf, "Phillipsite and Al- tobermorite Mineral Cements Produced through Low-Temperature Water-Rock Reactions in Roman Marine Concrete" (2017). Geology Faculty Publications. 67. https://cedar.wwu.edu/geology_facpubs/67 This Article is brought to you for free and open access by the Geology at Western CEDAR. It has been accepted for inclusion in Geology Faculty Publications by an authorized administrator of Western CEDAR. For more information, please contact [email protected]. Authors Sean R. Mulcahy, Marie D. Jackson, Heng Chen, Yao Li, Piergiulio Cappelletti, and Hans-Rudolf Wenk This article is available at Western CEDAR: https://cedar.wwu.edu/geology_facpubs/67 American Mineralogist, Volume 102, pages 1435–1450, 2017 Phillipsite and Al-tobermorite mineral cements produced through low-temperature k water-rock reactions in Roman marine concrete MARIE D. JACKSON1,*, SEAN R. MULCAHY2, HENG CHEN3, YAO LI4, QINFEI LI5, PIERGIULIO CAppELLETTI6, 7 AND HANS-RUDOLF WENK 1Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah 84112, U.S.A.
  • Atomistic Modeling of Crystal Structure of Ca1.67Sihx

    Atomistic Modeling of Crystal Structure of Ca1.67Sihx

    Cement and Concrete Research 67 (2015) 197–203 Contents lists available at ScienceDirect Cement and Concrete Research journal homepage: http://ees.elsevier.com/CEMCON/default.asp Atomistic modeling of crystal structure of Ca1.67SiHx Goran Kovačević a, Björn Persson a, Luc Nicoleau b, André Nonat c, Valera Veryazov a,⁎ a Theoretical Chemistry, P.O.B. 124, Lund University, Lund 22100, Sweden b BASF Construction Solutions GmbH, Advanced Materials & Systems Research, Albert Frank Straße 32, 83304 Trostberg, Germany c Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, BP 47870, F-21078 Dijon Cedex, France article info abstract Article history: The atomic structure of calcium-silicate-hydrate (C1.67-S-Hx) has been investigated by theoretical methods in Received 13 February 2014 order to establish a better insight into its structure. Three models for C-S-H all derived from tobermorite are pro- Accepted 12 September 2014 posed and a large number of structures were created within each model by making a random distribution of silica Available online xxxx oligomers of different size within each structure. These structures were subjected to structural relaxation by ge- ometry optimization and molecular dynamics steps. That resulted in a set of energies within each model. Despite Keywords: an energy distribution between individual structures within each model, significant energy differences are Calcium-Silicate-Hydrate (C-S-H) (B) Crystal Structure (B) observed between the three models. The C-S-H model related to the lowest energy is considered as the most Atomistic simulation probable. It turns out to be characterized by the distribution of dimeric and pentameric silicates and the absence of monomers.
  • Brownmillerite Ca2(Al, Fe )2O5 C 2001-2005 Mineral Data Publishing, Version 1

    Brownmillerite Ca2(Al, Fe )2O5 C 2001-2005 Mineral Data Publishing, Version 1

    3+ Brownmillerite Ca2(Al, Fe )2O5 c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Orthorhombic. Point Group: mm2. As square platelets, to about 60 µm; massive. Physical Properties: Hardness = n.d. D(meas.) = 3.76 D(calc.) = 3.68–3.73 Optical Properties: Semitransparent. Color: Reddish brown. Optical Class: Biaxial (–). Pleochroism: Distinct; X = Y = yellow-brown; Z = dark brown. Orientation: Y and Z lie in the plane of the platelets; extinction in that plane is diagonal. α = < 2.02 β = > 2.02 γ = > 2.02 2V(meas.) = n.d. Cell Data: Space Group: Ibm2. a = 5.584(5) b = 14.60(1) c = 5.374(5) Z = 2 X-ray Powder Pattern: Near Mayen, Germany. 2.65 (vs), 7.19 (s), 2.78 (s), 1.93 (s), 2.05 (ms), 3.65 (m), 1.82 (m) Chemistry: (1) (2) (3) TiO2 1.5 1.9 Al2O3 17.2 22.3 13.1 Fe2O3 30.5 27.6 41.9 Cr2O3 0.1 n.d. MgO n.d. n.d. CaO 46.2 44.8 43.7 insol. 4.0 LOI 0.5 Total 94.4 100.3 100.6 (1) Near Mayen, Germany; by semiquantitative spectroscopy. (2) Hatrurim Formation, Israel; corresponds to Ca1.99(Al1.09Fe0.86Ti0.05)Σ=2.00O5. (3) Do.; corresponds to Ca1.95(Fe1.31Al0.64 Ti0.06)Σ=2.01O5. Occurrence: In thermally metamorphosed limestone blocks included in volcanic rocks (near Mayen, Germany); in high-temperature, thermally metamorphosed, impure limestones (Hatrurim Formation, Israel). Association: Calcite, ettringite, wollastonite, larnite, mayenite, gehlenite, diopside, pyrrhotite, grossular, spinel, afwillite, jennite, portlandite, jasmundite (near Mayen, Germany); melilite, mayenite, wollastonite, kalsilite, corundum (Kl¨och, Austria); spurrite, larnite, mayenite (Hatrurim Formation, Israel).
  • Canadian Mineralogist, 51

    Canadian Mineralogist, 51

    785 The Canadian Mineralogist Vol. 51, pp. 785-800 (2013) DOI : 10.3749/canmin.51.5.785 A COMBINED GEOCHEMICAL AND GEOCHRONOLOGICAL INVESTIGATION OF NIOCALITE FROM THE OKA CARBONATITE COMPLEX, CANADA WEI CHEN§, ANTONIO SIMONETTI, AND PETER C. BURNS* Department of Civil & Environmental Engineering & Earth Sciences, 156 Fitzpatrick Hall, University of Notre Dame, Notre Dame IN, 46556 USA ABSTRACT This study is the first to report a detailed geochemical investigation and in situ U-Pb ages for niocalite, which occurs within carbonatite from the Bond Zone area of the Oka Carbonatite Complex (Canada). Niocalite is a Nb-disilicate member of the låvenite−cuspidine group. The major element composition of the niocalite studied here is relatively homogeneous with the average formula of: (Na0.34Fe0.06Mn0.19Mg0.09Ca13.40REE0.15Ti0.02)Σ14.25Nb2.12Ta0.06(Si2O7)4O7.65F2.44. Niocalite is enriched in minor and trace elements [i.e., Ta, Ti, and rare earth elements (REEs) up to 4.35 wt.%], with double- and triple-valenced elements (i.e., Sr, Y, REEs) substituting at different Ca-occupied lattice sites. The chondrite-normalized REE patterns for niocalite are LREE-enriched (~104 times chondrite) and negatively sloped. In addition, niocalite has higher HREE contents compared to those for co-existing apatite from the identical carbonatite sample. This result is expected based on bond valence data because of differing cation sizes. In situ U-Pb ages for niocalite from three carbonatite samples obtained by LA-ICP-MS define a wide range of ages, between ~111 and ~133 Ma. Niocalite from one carbonatite sample yields a bimodal distribution with weighted mean 206Pb/238U ages of 110.1 ± 5.0 Ma and 133.2 ± 6.1 Ma, and overlap those of co-existing apatite for the same sample.
  • Effect of Mineralogical Changes on Mechanical Properties of Well Cement

    Effect of Mineralogical Changes on Mechanical Properties of Well Cement

    ARMA 19–1981 Well integrity of high temperature wells: Effect of mineralogical changes on mechanical properties of well cement TerHeege, J.H. and Wollenweber, J. TNO Applied Geosciences, Utrecht, the Netherlands Marcel Naumann Downloaded from http://onepetro.org/ARMAUSRMS/proceedings-pdf/ARMA19/All-ARMA19/ARMA-2019-1981/1133466/arma-2019-1981.pdf/1 by guest on 02 October 2021 Equinor ASA, Sandsli, Norway Pipilikaki, P. TNO Structural Reliability, Delft, the Netherlands Vercauteren, F. TNO Material Solutions, Eindhoven, the Netherlands This paper w as prepared for presentation at the 53rd US Rock Mechanics/Geomechanics Symposium held in New Y ork, NY , USA , 23–26 June 2019. This paper w as selected for presentation at the symposium by an ARMA Technical Program Committee based on a technical and critical review of the paper by a minimum of tw o technical reviewers. The material, as presented, does not necessarily reflect any position of ARMA, its of ficers, or members. ABSTRACT: Wells used for steam-assisted gravity drainage (SAGD), for cyclic steam stimulation (CSS), for hydrocarbon production in areas with anomalous high geothermal gradient, or for geothermal energy extraction all are operated in high temperature environments where maintaining long term wellbore integrity is one of the key challenges. Changes in cement mineralogy and associated mechanical properties may critically affect the integrity of high temperature wells. In this study, the relation between changes in mineralogy and mechanical properties of API class G cement with 40% silica flour was investigated by exposing samples for 1-4 weeks to temperatures of 60-420°C. The effect of mineralogical changes on mechanical properties was investigated using a combination of chemical and microstructural analysis and triaxial strength tests at confining pressures of 2-15 MPa.
  • 51St Annual Franklin-Sterling Gem and Mineral Show

    51St Annual Franklin-Sterling Gem and Mineral Show

    ANNUAL Franklin - Sterling GEM & MINERAL SHOW SATURDAY & SUNDAY SEPTEMBER 29th & 30th, 2007 Sponsored By ;FRANKLIN. MI M I ; I' N 1 S F E R i U A i ■ N I I, '.--...., - Franklin, New Jersey The Fluorescent Mineral Capital Of The World STERLING HILL MINING MUSEUM 30 PLANT STREET OGDENSBURG, NJ 07439-1126 Welcome to The Sterling Hill Mine in Ogdensburg, NJ UNDERGROUND MINE TOURS • • • PASSAIC & NOBLE PIT • • COLLECTING OPEN TO THE PUBLIC • • • • During the Franklin-Sterling Hill Mineral Show, Sept. 30, 2007 • • Open Sunday, 9 AM to 3 PM • Admission: $5.00 per person, $1.50 per pound for anything taken • • • • • • STERLING HILL GARAGE SALE • • • • September 29th and 30th • Saturday and Sunday, from 11 AM to 3 PM • FRANKLIN MINE TOUR ADMISSION Citi N a. ADULT 10.00 CHILDREN (UNDER 12) 7.50 SENIOR CITIZEN (65+) 9.00 HOURS STERLING HILL OPEN 7 DAYS A WEEK MINING MUSEUM NEW YORK HOURS 10 AM TO 3 PM TOURS AT 1:00 PM DAILY OGDENSBURG & OTHER TIMES BY CHANCE I OR APPOINTMENT (:) GREEN THUMB FROM APRIL 1 TO NOV. 30 NURSERY MARCH AND DEC., WEEKENDS ONLY OTHER TIMES BY APPOINTMENT SPARTA JAN AND FEB., WEEKENDS ONLY FRANKLIN OTHER TIMES BY APPOINTMENT EXIT Nite Collecting Sat. Sept. 29th from 6-11 PM GROUP RATES AVAILABLE EXIT 34B For information call DOVER (973)209-7212 COLLECTING AVAILABLE FAX 973-209-8505 7 Days A Week, April to Nov. 10 AM to 3 PM www.sterlinghill.org MINERAL SPECIES FOUND AT FRANKLIN-STERLING HILL, NJ (Revised by FOMS Mineral List Committee September 2007) Acanthite Birnessite Cuprite Actinolite Bornite Cuprostibite Adamite Bostwickite
  • Bentorite Ca6(Cr, Al)2(SO4)3(OH)12 • 26H2O C 2001-2005 Mineral Data Publishing, Version 1

    Bentorite Ca6(Cr, Al)2(SO4)3(OH)12 • 26H2O C 2001-2005 Mineral Data Publishing, Version 1

    Bentorite Ca6(Cr, Al)2(SO4)3(OH)12 • 26H2O c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Hexagonal. Point Group: 6/m 2/m 2/m. As stout hexagonal prisms, {1010}, {1011}, {0001}, to 0.25 mm; commonly in fibrous masses, granular aggregates, and thin films. Twinning: On {1010} as composition plane. Physical Properties: Cleavage: {1010}, perfect; {0001}, distinct. Hardness = 2 D(meas.) = 2.025 D(calc.) = 2.021 Optical Properties: Transparent. Color: Bright violet. Streak: Very pale violet. Luster: Vitreous. Optical Class: Uniaxial (+). Pleochroism: O = nearly colorless; E = pale violet. Absorption: O < E. ω = 1.478(2) = 1.484(2) Cell Data: Space Group: P 63/mmc. a = 22.35 c = 21.41 Z = 8 X-ray Powder Pattern: Hatrurim Formation, Israel. 9.656 (100), 5.592 (40), 1.942 (20), 3.60 (10), 3.23 (10), 2.772 (10), 3.89 (8) Chemistry: (1) SO3 14.99 CO2 6.70 SiO2 2.50 Al2O3 1.01 Fe2O3 0.10 Cr2O3 7.48 MgO 0.00 CaO 29.90 H2O 37.70 Total 100.38 (1) Hatrurim Formation, Israel; by AA, SO3 by gravimetric analysis, CO2 and H2O by TGA; after deduction of CaO and CO2 as calcite and CaO, SiO2, H2O as truscottite, the remainder 3+ • (about 80%) corresponds to Ca5.88(Cr1.61Al0.32Fe0.02)Σ=1.95(S1.02O4)3.00(OH)11.97 28.06H2O. Mineral Group: Ettringite group. Occurrence: In low-temperature hydrothermal veins in black calcite–spurrite marble. Association: Calcite, thaumasite, truscottite, vaterite, jennite, tobermorite, brownmillerite, mayenite, melnikovite, “chlorite”. Distribution: In a marble quarry in the Hatrurim Formation, near the Arad-Sodom road, Negev Desert, Israel.
  • Evidence for the Alkaline Nature of Parental Carbonatite Melts at Oka Complex in Canada

    Evidence for the Alkaline Nature of Parental Carbonatite Melts at Oka Complex in Canada

    ARTICLE Received 22 Apr 2013 | Accepted 30 Sep 2013 | Published 30 Oct 2013 DOI: 10.1038/ncomms3687 Evidence for the alkaline nature of parental carbonatite melts at Oka complex in Canada Wei Chen1, Vadim S. Kamenetsky2 & Antonio Simonetti1 The Earth’s sole active carbonatite volcano, Oldoinyo Lengai (Tanzania), is presently erupting unique natrocarbonatite lavas that are characterized by Na- and K-bearing magmatic car- bonates of nyerereite [Na2Ca(CO3)2] and gregoryite [(Na2,K2,Ca)CO3]. Contrarily, the vast majority of older, plutonic carbonatite occurrences worldwide are dominated by Ca-(calcite) or Mg-(dolomite)-rich magmatic carbonates. Consequently, this leads to the conundrum as to the composition of primary, mantle-derived carbonatite liquids. Here we report a detailed chemical investigation of melt inclusions associated with intrusive (plutonic) calcite-rich carbonatites from the B120 Ma carbonatite complex of Oka (Canada). Melt inclusions are hosted by magnetite (Fe3O4), which crystallizes through a significant period of carbonatite melt solidification. Our results indicate mineral assemblages within the melt inclusions that are consistent with those documented in natrocarbonatite lavas. We propose therefore that derivation of alkali-enriched parental carbonatite melts has been more prevalent than that preserved in the geological record. 1 Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, Indiana 46556, USA. 2 ARC Centre of Excellence in Ore Deposits and School of Earth Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia. Correspondence and requests for materials should be addressed to W.C. (email: [email protected]). NATURE COMMUNICATIONS | 4:2687 | DOI: 10.1038/ncomms3687 | www.nature.com/naturecommunications 1 & 2013 Macmillan Publishers Limited.
  • Mayenite Ca12al14o33 C 2001-2005 Mineral Data Publishing, Version 1

    Mayenite Ca12al14o33 C 2001-2005 Mineral Data Publishing, Version 1

    Mayenite Ca12Al14O33 c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Cubic. Point Group: 43m (synthetic). In rounded anhedral grains, to 60 µm. Physical Properties: Hardness = n.d. D(meas.) = 2.85 D(calc.) = [2.67] Alters immediately to hydrated calcium aluminates on exposure to H2O. Optical Properties: Transparent. Color: Colorless. Optical Class: Isotropic. n = 1.614–1.643 Cell Data: Space Group: I43d (synthetic). a = 11.97–12.02 Z = 2 X-ray Powder Pattern: Near Mayen, Germany. 2.69 (vs), 4.91 (s), 2.45 (ms), 3.00 (m), 2.19 (m), 1.95 (m), 1.66 (m) Chemistry: (1) (2) (3) SiO2 0.4 Al2O3 45.2 49.5 51.47 Fe2O3 2.0 1.5 MnO 1.4 CaO 45.7 47.0 48.53 LOI 2.2 Total 95.1 99.8 100.00 (1) Near Mayen, Germany; by semiquantitative spectroscopy. (2) Hatrurim Formation, Israel; by electron microprobe, corresponding to (Ca11.7Mg0.5)Σ=12.2(Al13.5Fe0.25Si0.10)Σ=13.85O33. (3) Ca12Al14O33. Occurrence: In thermally metamorphosed limestone blocks included in volcanic rocks (near Mayen, Germany); common in high-temperature, thermally metamorphosed, impure limestones (Hatrurim Formation, Israel). Association: Calcite, ettringite, wollastonite, larnite, brownmillerite, gehlenite, diopside, pyrrhotite, grossular, spinel, afwillite, jennite, portlandite, jasmundite (near Mayen, Germany); melilite, wollastonite, kalsilite, brownmillerite, corundum (Kl¨och, Austria); spurrite, larnite, grossite, brownmillerite (Hatrurim Formation, Israel). Distribution: From the Ettringer-Bellerberg volcano, near Mayen, Eifel district, Germany. Found at Kl¨och, Styria, Austria. In the Hatrurim Formation, Israel. From Kopeysk, Chelyabinsk coal basin, Southern Ural Mountains, Russia. Name: For Mayen, Germany, near where the mineral was first described.
  • Kirschsteinite Cafe Sio4 C 2001 Mineral Data Publishing, Version 1.2 ° Crystal Data: Orthorhombic

    Kirschsteinite Cafe Sio4 C 2001 Mineral Data Publishing, Version 1.2 ° Crystal Data: Orthorhombic

    2+ Kirschsteinite CaFe SiO4 c 2001 Mineral Data Publishing, version 1.2 ° Crystal Data: Orthorhombic. Point Group: 2=m 2=m 2=m: In crystals, to 0.5 mm; as skeletal rims on other minerals; crystalline massive. Physical Properties: Hardness = n.d. D(meas.) = 3.434 D(calc.) = 3.596 Optical Properties: Transparent. Color: Pale green; colorless in thin section. Optical Class: Biaxial ({). Orientation: X = b; Y = c; Z = a. ® = 1.660{1.689 ¯ = 1.720 ° = 1.694{1.728 2V(meas.) = 51(1)± 2V(calc.) = 53±{61± Cell Data: Space Group: [P bnm] (by analogy to the olivine group). a = 4.859 b = 11.132 c = 6.420 Z = 4 X-ray Powder Pattern: Mt. Shaheru, Congo. 2.949 (100), 2.680 (85), 2.604 (80), 3.658 (70), 1.830 (60), 2.414 (40), 5.569 (35) Chemistry: (1) (2) SiO2 32.71 31.96 TiO2 0.23 Al2O3 0.26 Fe2O3 0.66 FeO 29.34 38.21 MnO 1.65 MgO 4.95 CaO 29.30 29.83 Na2O 0.34 K2O 0.36 + H2O 0.25 H2O¡ 0.06 P2O5 0.07 Total 100.18 100.00 (1) Mt. Shaheru, Congo. (2) CaFeSiO4: Polymorphism & Series: Forms a series with monticellite. Occurrence: In melilite-nephelinite lava (Mt. Shaheru, Congo); in calcareous skarn (Tazheran massif, Russia). Association: Melilite, nepheline, clinopyroxene, kalsilite, gÄotzenite, combeite, sodalite, magnetite, perovskite, apatite, \hornblende," biotite (Mt. Shaheru, Congo); titanian augite, wollastonite, melilite, garnet, calcite, cuspidine, diopside, perovskite, troilite, graphite (Tazheran massif, Russia). Distribution: On Mt. Shaheru, the extinct southern cone of Mt. Nyiragongo, Kivu Province, Congo (Zaire).
  • Wollastonite Paper Revised -Symplectic.Pdf

    Wollastonite Paper Revised -Symplectic.Pdf

    This is a repository copy of Thermal stability of C-S-H phases and applicability of Richardson and Groves’ and Richardson C-(A)-S-H(I) models to synthetic C-S-H. White Rose Research Online URL for this paper: http://eprints.whiterose.ac.uk/109873/ Version: Accepted Version Article: Rodriguez, ET, Garbev, K, Merz, D et al. (2 more authors) (2017) Thermal stability of C-S-H phases and applicability of Richardson and Groves’ and Richardson C-(A)-S-H(I) models to synthetic C-S-H. Cement and Concrete Research, 93. pp. 45-56. ISSN 0008-8846 https://doi.org/10.1016/j.cemconres.2016.12.005 © 2016 Published by Elsevier Ltd. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ Reuse Unless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version - refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher’s website. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request.
  • Calcium-Aluminum-Silicate-Hydrate &#X201c

    Calcium-Aluminum-Silicate-Hydrate “

    Cent. Eur. J. Geosci. • 2(2) • 2010 • 175-187 DOI: 10.2478/v10085-010-0007-6 Central European Journal of Geosciences Calcium-aluminum-silicate-hydrate “cement” phases and rare Ca-zeolite association at Colle Fabbri, Central Italy Research Article F. Stoppa1∗, F. Scordari2,E.Mesto2, V.V. Sharygin3, G. Bortolozzi4 1 Dipartimento di Scienze della Terra, Università G. d’Annunzio, Chieti, Italy 2 Dipartimento Geomineralogico, Università di Bari, Bari, Italy 3 Sobolev V.S. Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia 4 Via Dogali, 20, 31100-Treviso Received 26 January 2010; accepted 8 April 2010 Abstract: Very high temperature, Ca-rich alkaline magma intruded an argillite formation at Colle Fabbri, Central Italy, producing cordierite-tridymite metamorphism in the country rocks. An intense Ba-rich sulphate-carbonate- alkaline hydrothermal plume produced a zone of mineralization several meters thick around the igneous body. Reaction of hydrothermal fluids with country rocks formed calcium-silicate-hydrate (CSH), i.e., tobermorite- afwillite-jennite; calcium-aluminum-silicate-hydrate (CASH) – “cement” phases – i.e., thaumasite, strätlingite and an ettringite-like phase and several different species of zeolites: chabazite-Ca, willhendersonite, gismon- dine, three phases bearing Ca with the same or perhaps lower symmetry of phillipsite-Ca, levyne-Ca and the Ca-rich analogue of merlinoite. In addition, apophyllite-(KF) and/or apophyllite-(KOH), Ca-Ba-carbonates, portlandite and sulphates were present. A new polymorph from the pyrrhotite group, containing three layers of sphalerite-type structure in the unit cell, is reported for the first time. Such a complex association is unique.