DOCSLIB.ORG

THE MICROHARDNESS of OPAQUE MINERALS VOL.I THESIS Submitted by B.B. YOUNG, B.Sc., A.R.S.M. Degree of Doctor of Philosophy In

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

THE MICROHARDNESS OF OPAQUE MINERALS VOL.I THESIS Submitted by B.B. YOUNG, B.Sc., A.R.S.M. Degree of Doctor of Philosophy in the Faculty of Science UNIVERSITY OF LONDON April, 1961 Department of Mining Geology, Imperial College, London. I CONTENTS VOL. 1 Page No. Abstracts 1 Acknowledgements 4 Introduction 5 Chapter I. THEORY OF HARDNESS 9 A. General 9 B. Nature of the bonding forces 10 C. Hardness in relation to polishing 14 D. Assessement of hardness 16 E. Microhardness testing instruments 22 Chapter II. EXPERIMENTAL PROCEDURE 25 A. Methods of mounting sections 25 B. Relative merits of the mounting media used 30 C. Grinding and polishing techniques 32 D. Orientation of sections 36 E. Measurement of microhardness 44 F. Routine procedure 42 G. Accuracy and renroducibility of results 45 11 Page No. Chapter III. VARIATION OF MICROHARDNESS WITH LOAD 53 A. Variation of microhardness values with load 53 (a)General 53 (b)Results 60 (c)Discussion of the results 69 (d)Conclusions 77 B. The relation between load and grain size 78 (a)General 78 (b)Discussion 80 C. Variation of the deformation characteristics with load 88 Chapter IV. VARIATION OF MICROHATNESS WITH ORIENTATION 90 A. General 90 B. Microhardness values determined from randomly oriented sections 91 C. The relation, during indentation, between deformation processes and orientation 104 D. Microhardness values obtained on oriented sections of mineral 110 (a)General 110 (b)Discussion of the results 111 (i) Isometric minerals 111 (ii) Tetragonal minerals 130 (iii)Hexagonal mineral 139 iii Page No. (iv) Orthorhombic minerals 150 (v) Monoclinic minerals 163 (vi) Triclinic mineral E. Variation of microhardness on particular cryatal faces 169 (a) General 169 (h) Theory 169 (c) Results and discussion 174 (1) Isometric minerals 174 (ii) Tetragonal minerals 181 (iii)Hexagonal minerals 183 (iv) Orthorhombic minerals 192 (v) Monoclinic minerals 207 (vi) Triclinic minerals 209 F. The variations of Knoo,D microhardness with reflectivity on particular crystal faces. 211 G. Variation of the diagonal lengths of Vickers indentation on rotation of the indenter on particular crystal faces 213 (a)Minerals whose crystals have been accurately oriented 211+ (b)Minerals whose orientations were not precisely known 218 (c)General discussion 218 iv Page No, Chapter V. THE SHAPE AND ASSOCIATED CHARACTERISTICS OF TH2, INDENCATIONS 223 A. General 223 B. Variation in the shape of indentations 224 C. Variations in the dimensions of inden- tations 228 D. Associated deformation characteristics 229 E. Features of plastic deformation 230 F. Fracturing Phenomena 231 G. V7riations of the shape and deformation characteristics with orientation 235 H. Variations of the shape and deformation characteristics of indentations with mineral species 241 I. The relationship of indentation character- istics to atomic structure 254 Chapter VI. VARIATION OF MICROHATDNESS WITH CHANGES OF CHEICAL COMPOSITION 267 A. Introduction 267 B. Microhardness variations in chemically analysed isomorphous. series 269 C. Microhardness differences between end members of isomorphous or isostructural series 281+ D. Variations of microhardness with chemical composition between different mineral species 296 Page No. Chapter VII. SYSTEMATIC MICROHARDNESS DATA 311 A. Accuracy and reproducibility of the results 311 B. Comparison of the microhardneqs v2lues with established Mohs and Talmage hardness values 316 C. Comparison of Vickers microhardness and reflectivity results 331 D. Comparison of other physical properties of minerals with microhardness values 341 E. The relationship between microhardness, paragenetic sequence, and temperature of formation 345 F. Crystallochemical factors controlling micro- hardness 351 Chapter VIII. MINERALOGICAL APPLICATIONS OF MICROHARDNESS TESTING TECHNIQUES 359 Chapter IX. GENERAL CONCLUSIONS 364 References 378 Anpendix A. Photographs of Indentation 387 Characteristics Appendix. B. 413 vi VOL. II Page No. Introduction 417 Mineral Authentication 419 Abbreviations 420 References 422 RESULTS 423 vii List of Tables Page No I-IV A-X Distance and hardness 12 V Effect of mounting method on microhardness values 31 VI Microhardness values on and off stage 39 VII Effect of number of measurements on the probable error of the microhardness 52 VIII Relationship of orientation to the microhard= ness and logarithmic index - Galena (Vickers indenter) 55 IX Relationship of oreitnation to the micro- hardness and logarithmic index - Galena ' (Knoop indenter) 56 X Relationship of orientation to the microhard- ness and logarithmic index - Sphalerite (Vickers and Knoop)indenters) 57 XI Relationship of orientation to the micro- hardness and logarithmic index - other minerals 58, 59 XII Probable errors of the mean microhardness values and logarithmic indices 62 XIII Variation of microhardness with load on oriented sections of 10 minerals 70 . XIV-XV Effect of error in measurement of the diagonal length on the microhardness 72 XVI Optimum load dependent upon the hardness of the minerals 79 XVII Minimum Grain sizes 81 - 86 XVIII Systematic Microhardness Data 92 - 99 viii Page No. XIX Variation of the microhardness anisotropism 102 of minerals with crystal system XX Comparison of indentation and scratch micro- hardness values on the (100, (110) and (111) faces of galena 113 XXI Oriented microhardness w,lues obtained on some members of the spinel minerals 124 XXII Oriented microhardness values obtained on Gold, Conoer and Cuprite 125 XXIII Oriented microhardness values 126 - 129 XXIV The variation of microhardness and reflec- tivity values with orientation 133 - 138 XXV Comparison of the microhardness values 144 obtained by Bowie and Taylor (1958) and the present writer, on oriented sections of pyrrhotite XXVI A comparison of reflectivity and micro- hardness differences on the basal (0001) and orism (1010) faces of six hexagonal minerals 147 XXVII % Knoop microhardness anisotropism on six hexagonal minerals 188 XXVIII Comparison of Knoop microhardness maxima and minima with reflectivity maxima and minima - Hexagonal 204 XXIX Comparison of Knoop microhardness and reflectivity maxima and minima - Tetragonal and Monoclinic 205 XXX Comparison of Knoop microhardness and reflectivity maxima and minima - Orthorhombic 206 XXXI The relationship of the elongation of indentations to movement planes 221 - 222 ix Page No, XXXII Examples of minerals showing different indentation types 225 XXXIII Examples of minerals whose indentations show different degrees of "anisotropism" 226 XXXIV Translation data deduced from the present studeies 262 - 264 XXXV Deformation characteristics of the main mineral groups 265 - 266 XXXVI Microhardness mean values for 10 analysed sphalcrites 270 XXXVII Microhardness values obtained on 10 analysed huebnerite-ferbr:rites 275 XXXVIII Micrqhardness values obtained on 7 analysed columbite-tantalites 277 XXXIX Microhardness values - Native elements 298 XL Microhardness values - Sulphides, selenides and tellurides 299 - 300 XLI Microhardness values - Arsenides, antimonides, suloharsenides and sulphantimonides 301 XLII Microhardness values - Sulphosalts 302 XLIII Microhardness values - Oxides, Hydroxides 303 - 304 XLIV Microhardness values - Carbonates, phosphates 305 XLV Ionic and atomic radii - After Evans (1939) 306 YLVI Tetrahedral atomic radii - After Pauling and Huggins (1934) 307 XLVII Variation in microhardness with chemical composition in some cobalt-hearing analogues of pentlandite 308 XLVIII Comparison of calculated and actual hardness values for niccolite and breithauptite (After Povarennykh, 1959) 308 x Page No. XLIX The variation of microhardness with chemical composition in some copper iron sulphides 309 L The variation of microhardness with chemical composition in some lead sulpho- salt minerals. 309 LI The relationship between crystal system and microhardness in minerals having the compositions - ZnS and FeS2 310 LII Vickers and Knoop microhardness values for the standard Mohs scale minerals 318 LIII A comparison of Vickers mean microhardness data 319 LIV Microhardness values obtained on the standard Mohs scale minerals - After Povarennykh (1959) 322 LV Microhardness values extrapolated from Mohs and/or Talmage values 325 - 328 LVI Microhardness values extrapolated from polishing hardness data 329 - 330 LVII The relationship between bonding and the physic .l properties of minerals 344 LVIII The relationship between structure, bonding, valency, microhardness and paragenetic sequence of sulphides 347 LIX Relationship between temperatures of formation of minerals and their hardness values 349 - 350 LX A comparison of calculated and measured microhardness values 356. -1- ABSTRACT Knoop and Vickers microhardness values have been determined at different loads for over 200 mineral species. The microhardness data have been applied to a system of mineral identification, and some of the more theoretical problems associated with mineral hardness have been investi- gated. Although the minerals studied exhibited considerable variation in microhardness, the determination of the micro- hardness and reflectivity ranges and their mean values was found to be diagnostic for most of the minerals studied. Methods of mounting polished sections were investigated, and microhardness values of softer minerals have been shown to be appreciably affected by the stresses involved in thermoplastic methods. Cold-setting plastic mounting media were used in the present studies. The microhardness values were found to be strongly dependent upon
Recommended publications
  • Xrd and Tem Studies on Nanophase Manganese

    Xrd and Tem Studies on Nanophase Manganese

    Clays and Clay Minerals, Vol. 64, No. 5, 488–501, 2016. 1 1 2 2 3 XRD AND TEM STUDIES ON NANOPHASE MANGANESE OXIDES IN 3 4 FRESHWATER FERROMANGANESE NODULES FROM GREEN BAY, 4 5 5 6 LAKE MICHIGAN 6 7 7 8 8 S EUNGYEOL L EE AND H UIFANG X U* 9 9 NASA Astrobiology Institute, Department of Geoscience, University of Wisconsin Madison, Madison, 10 À 10 1215 West Dayton Street, A352 Weeks Hall, Wisconsin 53706 11 11 12 12 13 Abstract—Freshwater ferromanganese nodules (FFN) from Green Bay, Lake Michigan have been 13 14 investigated by X-ray powder diffraction (XRD), micro X-ray fluorescence (XRF), scanning electron 14 microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and scanning 15 transmission electron microscopy (STEM). The samples can be divided into three types: Mn-rich 15 16 nodules, Fe-Mn nodules, and Fe-rich nodules. The manganese-bearing phases are todorokite, birnessite, 16 17 and buserite. The iron-bearing phases are feroxyhyte, goethite, 2-line ferrihydrite, and proto-goethite 17 18 (intermediate phase between feroxyhyte and goethite). The XRD patterns from a nodule cross section 18 19 suggest the transformation of birnessite to todorokite. The TEM-EDS spectra show that todorokite is 19 associated with Ba, Co, Ni, and Zn; birnessite is associated with Ca and Na; and buserite is associated with 20 2+ +2 3+ 20 Ca. The todorokite has an average chemical formula of Ba0.28(Zn0.14Co0.05 21 2+ 4+ 3+ 3+ 3+ 2+ 21 Ni0.02)(Mn4.99Mn0.82Fe0.12Co0.05Ni0.02)O12·nH2O.
  • Metamorphism of Sedimentary Manganese Deposits

    Metamorphism of Sedimentary Manganese Deposits

    Acta Mineralogica-Petrographica, Szeged, XX/2, 325—336, 1972. METAMORPHISM OF SEDIMENTARY MANGANESE DEPOSITS SUPRIYA ROY ABSTRACT: Metamorphosed sedimentary deposits of manganese occur extensively in India, Brazil, U. S. A., Australia, New Zealand, U. S. S. R., West and South West Africa, Madagascar and Japan. Different mineral-assemblages have been recorded from these deposits which may be classi- fied into oxide, carbonate, silicate and silicate-carbonate formations. The oxide formations are represented by lower oxides (braunite, bixbyite, hollandite, hausmannite, jacobsite, vredenburgite •etc.), the carbonate formations by rhodochrosite, kutnahorite, manganoan calcite etc., the silicate formations by spessartite, rhodonite, manganiferous amphiboles and pyroxenes, manganophyllite, piedmontite etc. and the silicate-carbonate formations by rhodochrosite, rhodonite, tephroite, spessartite etc. Pétrographie and phase-equilibia data indicate that the original bulk composition in the sediments, the reactions during metamorphism (contact and regional and the variations and effect of 02, C02, etc. with rise of temperature, control the mineralogy of the metamorphosed manga- nese formations. The general trend of formation and transformation of mineral phases in oxide, carbonate, silicate and silicate-carbonate formations during regional and contact metamorphism has, thus, been established. Sedimentary manganese formations, later modified by regional or contact metamorphism, have been reported from different parts of the world. The most important among such deposits occur in India, Brazil, U.S.A., U.S.S.R., Ghana, South and South West Africa, Madagascar, Australia, New Zealand, Great Britain, Japan etc. An attempt will be made to summarize the pertinent data on these metamorphosed sedimentary formations so as to establish the role of original bulk composition of the sediments, transformation and reaction of phases at ele- vated temperature and varying oxygen and carbon dioxide fugacities in determin- ing the mineral assemblages in these deposits.
  • 1 CRYSTAL CHEMISTRY of SELECTED Sb, As and P MINERALS

    1 CRYSTAL CHEMISTRY of SELECTED Sb, As and P MINERALS

    Crystal Chemistry of Selected Sb, As, and P Minerals Item Type text; Electronic Dissertation Authors Origlieri, Marcus Jason Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 07/10/2021 10:49:41 Link to Item http://hdl.handle.net/10150/194240 1 CRYSTAL CHEMISTRY OF SELECTED Sb, As AND P MINERALS by Marcus Jason Origlieri ___________________________________________ A Dissertation Submitted to the Faculty of the DEPARTMENT OF GEOSCIENCES In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 2005 2 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Dissertation Committee, we certify that we have read the dissertation prepared by Marcus Jason Origlieri entitled Crystal Chemistry of Selected Sb, As, and P Minerals and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy _______________________________________________________________________ Date: November 15, 2005 Robert T. Downs _______________________________________________________________________ Date: November 15, 2005 M. Bonner Denton _______________________________________________________________________ Date: November 15, 2005 Mihai N. Ducea _______________________________________________________________________ Date: November 15, 2005 Charles T. Prewitt Final approval and acceptance of this dissertation is contingent upon the candidate’s submission of the final copies of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement.
  • Jacobsite from the Tamworth District of New South Wales

    Jacobsite from the Tamworth District of New South Wales

    538 Jacobsite from the Tamworth district of New South Wales. By F .L. STILLWELL, D.Sc., and A. B. EDWAP~DS,D.Sc., Ph.D., D.I.C. Commonwealth Scientific and Industrial Organization, Melbourne. [Taken as read November 2, 1950.] WO new occurrences of the rare manganese mineral jacobsite T (MnF%0~) have come to light in the course of mineragraphic studies carried out as part of the research programme of the Mineragraphic Section of the Commonwealth Scientific and Industrial Research Organization. The jacobsite occurs as a constituent of small bodies of high-grade manganese ore at Weabonga, near Danglemah, and at the Mount Sally mine, about 6 miles west of Danglemah, both in the Tam- worth district of New South Wales. The deposits occur in altered sediments, within a mile or two of a granite contact. 1 They are irregular lenticular veins ranging from a few inches to several feet in thickness, between altered slate walls. The veins do not exceed a length of 200-300 feet. The lode material consists of manganese oxides, chiefly psilomelane and pyrolusite, associated with quartz, rhodonite, and iron oxide. The manganese oxides are mainly supergene, and although the deposits are of high grade near the surface, it is doubtful whether they can be worked below the depths of 50- 60 feet, owing to the increase in the amount of rhodonite and quartz relative to manganese oxides at this depth. In the Weabonga ore the jacobsite occurs as narrow seams and lenticles, about 0.5 cm. across, and 3.0 cm. long enclosed in, and partly replaced by, pyrolusite and psilomelane.
  • Washington State Minerals Checklist

    Washington State Minerals Checklist

    Division of Geology and Earth Resources MS 47007; Olympia, WA 98504-7007 Washington State 360-902-1450; 360-902-1785 fax E-mail: [email protected] Website: http://www.dnr.wa.gov/geology Minerals Checklist Note: Mineral names in parentheses are the preferred species names. Compiled by Raymond Lasmanis o Acanthite o Arsenopalladinite o Bustamite o Clinohumite o Enstatite o Harmotome o Actinolite o Arsenopyrite o Bytownite o Clinoptilolite o Epidesmine (Stilbite) o Hastingsite o Adularia o Arsenosulvanite (Plagioclase) o Clinozoisite o Epidote o Hausmannite (Orthoclase) o Arsenpolybasite o Cairngorm (Quartz) o Cobaltite o Epistilbite o Hedenbergite o Aegirine o Astrophyllite o Calamine o Cochromite o Epsomite o Hedleyite o Aenigmatite o Atacamite (Hemimorphite) o Coffinite o Erionite o Hematite o Aeschynite o Atokite o Calaverite o Columbite o Erythrite o Hemimorphite o Agardite-Y o Augite o Calciohilairite (Ferrocolumbite) o Euchroite o Hercynite o Agate (Quartz) o Aurostibite o Calcite, see also o Conichalcite o Euxenite o Hessite o Aguilarite o Austinite Manganocalcite o Connellite o Euxenite-Y o Heulandite o Aktashite o Onyx o Copiapite o o Autunite o Fairchildite Hexahydrite o Alabandite o Caledonite o Copper o o Awaruite o Famatinite Hibschite o Albite o Cancrinite o Copper-zinc o o Axinite group o Fayalite Hillebrandite o Algodonite o Carnelian (Quartz) o Coquandite o o Azurite o Feldspar group Hisingerite o Allanite o Cassiterite o Cordierite o o Barite o Ferberite Hongshiite o Allanite-Ce o Catapleiite o Corrensite o o Bastnäsite
  • Mineral Processing

    Mineral Processing

    Mineral Processing Foundations of theory and practice of minerallurgy 1st English edition JAN DRZYMALA, C. Eng., Ph.D., D.Sc. Member of the Polish Mineral Processing Society Wroclaw University of Technology 2007 Translation: J. Drzymala, A. Swatek Reviewer: A. Luszczkiewicz Published as supplied by the author ©Copyright by Jan Drzymala, Wroclaw 2007 Computer typesetting: Danuta Szyszka Cover design: Danuta Szyszka Cover photo: Sebastian Bożek Oficyna Wydawnicza Politechniki Wrocławskiej Wybrzeze Wyspianskiego 27 50-370 Wroclaw Any part of this publication can be used in any form by any means provided that the usage is acknowledged by the citation: Drzymala, J., Mineral Processing, Foundations of theory and practice of minerallurgy, Oficyna Wydawnicza PWr., 2007, www.ig.pwr.wroc.pl/minproc ISBN 978-83-7493-362-9 Contents Introduction ....................................................................................................................9 Part I Introduction to mineral processing .....................................................................13 1. From the Big Bang to mineral processing................................................................14 1.1. The formation of matter ...................................................................................14 1.2. Elementary particles.........................................................................................16 1.3. Molecules .........................................................................................................18 1.4. Solids................................................................................................................19
  • Chromium(III/VI) Binding to Magnetite (Fe3o4), Hausmannite (Mn3o4), and Jacobsite (Mnfe2o4) Nanomaterials

    Chromium(III/VI) Binding to Magnetite (Fe3o4), Hausmannite (Mn3o4), and Jacobsite (Mnfe2o4) Nanomaterials

    University of Texas at El Paso DigitalCommons@UTEP Open Access Theses & Dissertations 2010-01-01 Chromium(III/VI) Binding To Magnetite (Fe3O4), Hausmannite (Mn3O4), And Jacobsite (Mnfe2O4) Nanomaterials Jeffrey Edward Hernandez University of Texas at El Paso, [email protected] Follow this and additional works at: https://digitalcommons.utep.edu/open_etd Part of the Analytical Chemistry Commons, and the Environmental Sciences Commons Recommended Citation Hernandez, Jeffrey Edward, "Chromium(III/VI) Binding To Magnetite (Fe3O4), Hausmannite (Mn3O4), And Jacobsite (Mnfe2O4) Nanomaterials" (2010). Open Access Theses & Dissertations. 2499. https://digitalcommons.utep.edu/open_etd/2499 This is brought to you for free and open access by DigitalCommons@UTEP. It has been accepted for inclusion in Open Access Theses & Dissertations by an authorized administrator of DigitalCommons@UTEP. For more information, please contact [email protected]. CHROMIUM(III/VI) BINDING TO MAGNETITE (Fe 3O4), HAUSMANNITE (Mn 3O4), AND JACOBSITE (MnFe 2O4) NANOMATERIALS JEFFREY EDWARD HERNANDEZ Department of Chemistry APPROVED: ______________________________ Jorge Gardea-Torresdey, Ph.D. Chair ______________________________ Jose R. Peralta-Videa, Ph.D. ______________________________ Elizabeth J. Walsh, Ph.D. __________________________ Patricia D. Witherspoon, Ph.D. Dean of the Graduate School Copyright © By Jeffrey Edward Hernandez 2010 Dedication To GOD the father almighty To my beloved Beatrice To my mother Margarita, my sister Lorraine and my entire family “Science can purify religion from error and superstition; religion can purify science from idolatry and false absolutes. Each can draw the other into a wider world, a world in which both can flourish.... We need each other to be what we must be, what we are called to be.” Pope John Paul II CHROMIUM(III/VI) BINDING TO MAGNETITE (Fe 3O4), HAUSMANNITE (Mn 3O4), AND JACOBSITE (MnFe 2O4) NANOMATERIALS By JEFFREY HERNANDEZ, B.S.
  • List of New Mineral Names: with an Index of Authors

    List of New Mineral Names: with an Index of Authors

    415 A (fifth) list of new mineral names: with an index of authors. 1 By L. J. S~v.scs~, M.A., F.G.S. Assistant in the ~Iineral Department of the,Brltish Museum. [Communicated June 7, 1910.] Aglaurito. R. Handmann, 1907. Zeita. Min. Geol. Stuttgart, col. i, p. 78. Orthoc]ase-felspar with a fine blue reflection forming a constituent of quartz-porphyry (Aglauritporphyr) from Teplitz, Bohemia. Named from ~,Xavpo~ ---- ~Xa&, bright. Alaito. K. A. ~Yenadkevi~, 1909. BuU. Acad. Sci. Saint-P6tersbourg, ser. 6, col. iii, p. 185 (A~am~s). Hydrate~l vanadic oxide, V205. H~O, forming blood=red, mossy growths with silky lustre. Founi] with turanite (q. v.) in thct neighbourhood of the Alai Mountains, Russian Central Asia. Alamosite. C. Palaehe and H. E. Merwin, 1909. Amer. Journ. Sci., ser. 4, col. xxvii, p. 899; Zeits. Kryst. Min., col. xlvi, p. 518. Lead recta-silicate, PbSiOs, occurring as snow-white, radially fibrous masses. Crystals are monoclinic, though apparently not isom0rphous with wol]astonite. From Alamos, Sonora, Mexico. Prepared artificially by S. Hilpert and P. Weiller, Ber. Deutsch. Chem. Ges., 1909, col. xlii, p. 2969. Aloisiite. L. Colomba, 1908. Rend. B. Accad. Lincei, Roma, set. 5, col. xvii, sere. 2, p. 233. A hydrated sub-silicate of calcium, ferrous iron, magnesium, sodium, and hydrogen, (R pp, R',), SiO,, occurring in an amorphous condition, intimately mixed with oalcinm carbonate, in a palagonite-tuff at Fort Portal, Uganda. Named in honour of H.R.H. Prince Luigi Amedeo of Savoy, Duke of Abruzzi. Aloisius or Aloysius is a Latin form of Luigi or I~ewis.
  • Sugilite in Manganese Silicate Rocks from the Hoskins Mine and Woods Mine, New South Wales, Australia

    Sugilite in Manganese Silicate Rocks from the Hoskins Mine and Woods Mine, New South Wales, Australia

    Sugilite in manganese silicate rocks from the Hoskins mine and Woods mine, New South Wales, Australia Y. KAWACHI Geology Department, University of Otago, P.O.Box 56, Dunedin, New Zealand P. M. ASHLEY Department of Geology and Geophysics, University of New England, Armidale, NSW 2351, Australia D. VINCE 1A Ramsay Street, Essendon, Victoria 3040, Australia AND M. GOODWIN P.O.Bo• 314, Lightning Ridge, NSW 2834, Australia Abstract Sugilite relatively rich in manganese has been found at two new localities, the Hoskins and Woods mines in New South Wales, Australia. The occurrences are in manganese-rich silicate rocks of middle to upper greenschist facies (Hoskins mine) and hornblende hornfels facies (Woods mine). Coexisting minerals are members of the namansilite-aegirine and pectolite-serandite series, Mn-rich alkali amphiboles, alkali feldspar, braunite, rhodonite, tephroite, albite, microcline, norrishite, witherite, manganoan calcite, quartz, and several unidentified minerals. Woods mine sugilite is colour-zoned with pale mauve cores and colourless rims, whereas Hoskins mine sugilite is only weakly colour-zoned and pink to mauve. Within single samples, the chemical compositions of sugilite from both localities show wide ranges in A1 contents and less variable ranges of Fe and Mn, similar to trends in sugilite from other localities. The refractive indices and cell dimensions tend to show systematic increases progressing from Al-rich to Fe- Mn-rich. The formation of the sugilite is controlled by the high alkali (especially Li) and manganese contents of the country rock, reflected in the occurrences of coexisting high alkali- and manganese- bearing minerals, and by high fo2 conditions. KEYWORDS: sugilite, manganese silicate rocks, milarite group, New South Wales, Australia Introduction Na2K(Fe 3 +,Mn 3 +,Al)2Li3Sit2030.
  • Surface Area and Porosity Determination of Natural Todorokite

    Surface Area and Porosity Determination of Natural Todorokite

    NATIONAL AND KAPODISTRIAN UNIVERSITY OF ATHENS Surface area and porosity determination of natural todorokite- rich manganese (Mn) oxides, Cape Vani Mn deposit, Milos Island, Greece: implications for potential industrial applications By: Alexandra Stavropoulou A Thesis submitted in partial fullfilment of the requirements for the degree of Master of Science (M.Sc.) in the Faculty of Geology and Geoenvironment Supervisor: Prof. Stephanos P. Kilias January 2017 Master Thesis Stavropoulou V. Alexandra Examination Committee 1. Stephanos Kilias, Professor 2. Athanasios Godelitsas, Associate Professor 3. Ioannis Mitsis, Assistant Professor 2 Master Thesis Stavropoulou V. Alexandra ABSTRACT Natural todorokite-rich Mn oxide ore samples derived from the Cape Vani Mn oxide deposit, Milos Island, Greece, were studied by means of N2 BET specific surface area (SSA), and pore volume measurements. Cape Vani Mn oxide ores occur in a Pliocene- Pleistocene intravolcanic marine basin, they consist primarily of nanocrystalline and crystal defective todorokite, and δ-MnO2, hollandite-cryptomelane-coronadite- manjiroite and pyrolusite that cement volcaniclastic sandstone, and are suggested to be derived from biogenic Mn oxide precursors. Todorokite which possesses many potential technological and industrial applications, has been identified in Cape Vani employing primarily high-resolution transmission electron microscopy (HR-TEM) ; moreover, the Milos todorokite has identical nanoparticle morphology to experimentally produced todorokite from birnessite (Atkins et al., 2014) under conditions analogous to marine diagenetic and hydrothermal settings. The determined SSA and porosity were compared to available relevant data from the published literature, i.e. natural and synthetic todorokite in order to evaluate its industrial and/or environmental application prospects. The measured N2 BET surface areas of the sandstone-hosted Cape Vani material range from 10.7 to 53.1 m2/g, and correspond largely to Mn oxides and primarily todorokite.
  • Download the Scanned

    Download the Scanned

    American Mineralogist, Volume 77, pages 670475, 1992 NEW MINERAL NAMES* JonN L. J,Annson CANMET, 555 Booth Street,Ottawa, Ontario KIA OGl' Canada Abswurmbachite* rutile, hollandite, and manganoan cuprian clinochlore. The new name is for Irmgard Abs-Wurmbach, in recog- T. Reinecke,E. Tillmanns, H.-J. Bernhardt (1991)Abs- her contribution to the crystal chemistry, sta- wurmbachite, Cu'?*Mnl*[O8/SiOo],a new mineral of nition of physical properties ofbraunite. Type the braunite group: Natural occurrence,synthesis, and bility relations, and crystal structure.Neues Jahrb. Mineral. Abh., 163,ll7- material is in the Smithsonian Institution, Washington, r43. DC, and in the Institut fiir Mineralogie, Ruhr-Universitlit Bochum, Germany. J.L.J. The new mineral and cuprian braunit€ occur in brown- ish red piemontite-sursassitequartzites at Mount Ochi, near Karystos, Evvia, Greece, and in similar quartzites on the Vasilikon mountains near Apikia, Andros Island, Barstowite* Greece.An electron microprobe analysis (Andros mate- C.J. Stanley,G.C. Jones,A.D. Hart (1991) Barstowite, gave SiO, 9.8, TiO, rial; one of six for both localities) 3PbClr'PbCOr'HrO, a new mineral from BoundsClifl 0.61,Al,O3 0.60, Fe'O, 3.0,MnrO. 71.3,MgO 0.04,CuO St. Endellion,Cornwall. Mineral. Mag., 55, l2l-125. 12.5, sum 97.85 wto/o,corresponding to (CuStrMn3tu- Electron microprobe and CHN analysis gavePb75.47, Mgoo,)", oo(Mn3jrFe|jrAlo orTif.[nCuStr)", nrSi' o, for eight (calc.)6.03, sum 101.46wto/o, cations,ideally CuMnuSiO'r, the Cu analogueof braunite. Cl 18.67,C l.Iz,H 0.18,O to Pb.orClrrrCr.or- The range of Cu2* substitution for Mn2' is 0-42 molo/oin which for 17 atoms corresponds The min- cuprian braunite and 52-93 molo/oin abswurmbachite.
  • Petrology of Mn Carbonate–Silicate Rocks from the Gangpur Group, India

    Petrology of Mn Carbonate–Silicate Rocks from the Gangpur Group, India

    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by eprints@NML Journal of Asian Earth Sciences 25 (2005) 773–780 www.elsevier.com/locate/jaes Petrology of Mn carbonate–silicate rocks from the Gangpur Group, India B.K. Mohapatraa,*, B. Nayakb aRegional Research Laboratory (CSIR), Bhubaneswar 751 013, India bNational Metallurgical Laboratory (CSIR), Jamshedpur 831 007, India Received 11 April 2003; revised 6 February 2004; accepted 21 July 2004 Abstract Metamorphosed Mn carbonate–silicate rocks with or without oxides (assemblage I) and Mn silicate–oxide rocks with minor Mn carbonate (assemblage II) occur as conformable lenses within metapelites and metacherts of the Precambrian Gangpur Group, India. The petrology of the carbonate minerals: rhodochrosite, kutnahorite, and calcite that occur in these two assemblages is reported. Early stabilisation of spessartine, aegirine, quartz, and carbonates (in a wide solid solution range) was followed by pyroxmangite, tephroite, rhodonite through decarbonation reactions. Subsequently, jacobsite, hematite, braunite, hollandite and hausmannite have formed by decarbonation–oxidation processes during prograde metamorphism. Textural characteristics and chemical composition of constituent phases suggest that the mineral assemblages reflect a complex ! w relationship between protolithic composition, variation of XCO2 ( 0.2 to 0.3) and oxygen fugacity. A variation of XCO2 and fO2 would imply internal buffering of pore fluids through mineral reactions that produced diverse assemblages in the carbonate bearing manganiferous rocks. A minor change in temperature (from around 400 to 450 8C) does not appear to have had any major influence on the formation of different mineral associations. q 2004 Elsevier Ltd.