DOCSLIB.ORG

Synthesis of Barite, Celestite, Anglesite, Witherite, And

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Synthesis of Barite, Celestite, Anglesite, Witherite, And American Mineralogist, Volume 59, pages 1209-1219, 1974 Synthesisof Barite,Celestite, Anglesite, Witherite, and Strontianitefrom AqueousSolutions Cnenras W. BrouNr Departmentof Geology,Uniuersity of Georgia, Athens, Georgia30602 Abstract Well-formed single crystals of barite, strontium barite, celestite, and anglesite have been synthesized in gram quantities from dilute aqueous solutions in borosilicate glass flasks by a slow precipitation procedure over a range of experimental conditions. The largest crystals were grown in a 0.03 molar HCI solution, near 95"C in a non-uniformly heated flask by combining dilute metal chloride and sodium sulfate solutions at a rate of less than 5 mllhour. The optimum metal concentrations for growing large crystals were 0.01 molar for barite, O.02 molar for celestite, and 0.03 molar for anglesite. The optimum Na,SOr solution concentrations were 0.01 molar for barites and 0.02 molar for the other sulfates. Maximum dimensions for the thick tabular single crystals were 0.8 mm for barite, 1.2 mm for celestite, and2.3 mm for anglesite, In contrast amorphous or submicron-sized precipitates resulted from the use of more con- centrated solutions, too rapid a solution cornbination rate, the use of plastic ware, the use of magnetic stirring, inadequate cleaning of glassware,and uniform heating of the flask. For the carbonates,witherite and strontianite crystals over I mm long were grown in a flask designedto be completely filled with solution. The crystals were grown by combining 0.02 molar metal chloride and sodium bicarbonate solutions at a rate near 5 ml/hr. at 80"C in solutions that were initially 0.001 molar in HCl. Unlike the sulfate minerals, a uniformly heated flask resulted in larger carbonate crystals. The crystals of sulfate and carbonate minerals had the same indices of refraction as natural minerals. The spacing and intensities of powder diffraction peaks agreed with those published in the Powder Diffraction File for the minerals, fnhoduction the mineral is synthesizedas an analytical aid. Also, Many minerals that exhibit low solubilities in since synthetic crystals have a well developed ex- aqueoussolutions are difficult to synthesizein the ternal morphology, studies of crystal growth, dis- laboratory,especially when coarse,crystaUine ma- solution, and alteration can be made (Blount and terial is needed.As an alternative,the experimental- Beckrnan, 1974). ist may haveto usenatural materials that may be im- The initial objective of the synthesis studies re- pure becauseof ionic substitutionsor small foreign ported here was to develop a reliable procedure for inclusions.In many such experimentalstudies the making gram quantities of pure, coarsely crystalline presenceof theseimpurities and the chemicaleffects barite (BaSOa) for both hydrothermal solubility and that they may causeare neglected.In somechemical phase stability studies. Similarly, procedures were systems,the effectsproduced by impurities may be then developed for synthesizing anglesite (PbSO+), negligible;however, in other systemsthe effectsmay celestite (SrSoa), witherite (BaCOa), and strontia- be very large.For example,the presenceof strontium nite (SrCO3) from acqueous solutions at conditions in barite markedly affectsthe barium concentration similar to those that are believed to have precipitated in solutions(Gundlach, Stoppel, and Striibel, lg72). the natural minerals. Normally, however, precipi- The use of syntheticminerals of known high purity tates from aqueous solutions in the laboratory are that are chemically and structurally identical to the very fine grained, poorly crystalline, and tend to be naturalminerals would eliminatethe needto correct easily broken. An extensive survey of the literature for coprecipitatedimpurities or to justify ignoring was therefore undertaken to learn what factors may their presence.There are other advantasesalso. A be important for the synthesis of these minerals. radioactiveor isotopictracer could be idded when Large crystals of synthetic barite, celestite, and l2to CHARLES W. BLOUNT anglesitehave been producedby a number of pro- precipitatesof Sr, Ba, and Pb sulfateshas been used cedures.Frequently the experimentalsynthesis con- to prepare crystalline material with an averagesize ditions are far different from those under which near 10 microns (Nancollas,1968). Blount and the natural minerals are believedto have been pro- Dickson (1968) synthesizedcelestite with the same duced.For example,Patel and Bhat (1972) grew averagegrain size,but individual grainsranged from single crystalsof SrSO+and BaSO+up to 1 mm 1 to 120 microns in length. Recently, Brower long in silica gels at 20-35"C. Thesecrystals, how- (1973) used thermal cycling to grow synthetic ever, containedlarge amountsof silica, and their barite crystalsranging from 50 to 500 microns in perfection of external form diminished with in- length. Barites containing up to 20 mole percent creasingsize. Patel and Koshy (1968a) and Patel strontium were also synthesized.Up to 2 months and Bhat (1971) developedprocedures for growing of thermal cycling were required in experimentsthat crystalsof SrSO+and BaSO+from NaCl melts at yielded 5 to 7 milligrams of solid. A considerable temperaturesbetween 700 and 900'C that measured amount of finer material appearsto be presentin up to 7 mm long and 4 mm wide.-PbSO4crlstals the photographsin this paPer. of a poorer quality up to 2 mm long were grown Laitinen (1960) summarizedprevious studies on in NazSO+melts in a similar manner. While the the nucleation,growth, properties,and contamina- (011) and (102) faceswere recognized,photo- tion of BaSO+and other precipitatesused for gravi- graphs show the crystals to be quite irregular with metric analyses.While aimed at improving analytical a poorly developedmorphology. Moreover, the faces procedures,their studiesalso provided the type of of crystalsgrown by this procedureshowed a den- basicdata neededfor synthesizinghighly pure sul- dritic pattern which was not observedin any of the fates, as large and dense crystalline grains that samplesof natural material. This pattern was be- resist breakageand display a crystallinestructure lieved to have been produced by a rapid precipita- identicalto the correspondingnatural minerals.The tion of dissolvedmetal sulfatethat took placewhen two most important aspectsof these prior studies the flux solidified (Patel and Bhat, l97l). X-ray are the efforts ( 1) to reducethe numberof nuclea- diffractionmeasurements and hardnesstests gave the tion sites to promote the formation of a coarser same results for both natural and melt-grown crys- precipitateand (2) to reducecontamination by in- tals. The melt-grown crystals also showed fewer creasingcrystallinity. dislocationson etchedcleavage surfaces than natural The number of nucleationsites can be reduced materials (Patel and Koshy, 1968a, 1968b). in a number of ways. Nielsen (1957) found that A large amountof researchwork hasbeen under- careful cleaningof glasswareusing steam generated taken in efforts to improve aqueous precipitation from distilled water resultedin nearly a 10 fold progeduresthat are employedfor the determinations reductionin the numberof crystalsformed. Liteanu of barium and sulfate.The crystalsof BaSO+that and Lingner (I970a,1970b) used a hot alkaline are usually produced by rapid precipitation pro- Eore solution to accomplishthe same purpose. ceduresfrom aqueous solutions are small, l-20 Substancesthat catalyzethe nucleation of the pre- microns (Liteanu and Lingner, 1970a, l97Ob; cipitate also must be avoided.For exampleBricker Lieser, 1969). Crystalsproduced in this way are and Myers (1969) reported that Teflon catalyzed also easily broken yielding much finer material the precipitation of BaSO+.Pretreatment of the (Nielsen,1957; Fischer and Rhirlehammer,1953). solutionsused for the precipitationis alsoimportant. These precipitatesare therefore not suitable for O'Rourke and Johnson (1955) and Bogen and many types of experimentalstudies. Precipitates of Moyer (1956) both observedthat eitherfiltering or SrSO+and PbSO+have similar properties.Long aging the BaClz solutionsfor 24 ot more hours digestionperiods in hot aqueoussolutions have been reducedthe number of crystals l0-fold compared usedto recrystallizeand coarsenprecipitates. Mager to freshly preparedsolutions. They suggestedthat and Lieser (1972a,b,c) studied recrystallization aggregatesof incompletely dissolved BaCl2 may rates and the aging of SrSO+precipitates and con- have servedas nuclei for BaSOr crystals'The use cluded that the effects resultant from aging did of dilute solutionsis necessary.Liteanu and Lingner not stop even after a very long time. NazSO+that (1970a,b) studied the eftects of many different was occluded during the precipitation continued to experimentalconditions on BaSO+precipitates ob- be releasedas recrystallizationcontinued. Aging of tained using their rapid precipitation procedure. STNTIIES/S OF SULFATE AND CARBONATE MINERALS l2l1 Dependingupon the experimentalconditions, the Burkhard (1973) dissolvedaqueous precipitates averagegrain sizevaried between 1.2 and 6 microns. of barium and strontium sulfates in concentrated The largestgrains were producedin glasswarethat sulfuric acid and reprecipitatedthe solid by slowly had been carefully cleaned and by using dilute evaporatingthe acid at 160'C. (Ba,Sr)SOasolid solutions(below 0.001 molar) that had been aged, solution crystalsover the whole rangewere prepared filtered,or boiled prior to use. Mealor and Town- including pure
Load more

Recommended publications
  • Download PDF About Minerals Sorted by Mineral Name
    MINERALS SORTED BY NAME Here is an alphabetical list of minerals discussed on this site. More information on and photographs of these minerals in Kentucky is available in the book “Rocks and Minerals of Kentucky” (Anderson, 1994). APATITE Crystal system: hexagonal. Fracture: conchoidal. Color: red, brown, white. Hardness: 5.0. Luster: opaque or semitransparent. Specific gravity: 3.1. Apatite, also called cellophane, occurs in peridotites in eastern and western Kentucky. A microcrystalline variety of collophane found in northern Woodford County is dark reddish brown, porous, and occurs in phosphatic beds, lenses, and nodules in the Tanglewood Member of the Lexington Limestone. Some fossils in the Tanglewood Member are coated with phosphate. Beds are generally very thin, but occasionally several feet thick. The Woodford County phosphate beds were mined during the early 1900s near Wallace, Ky. BARITE Crystal system: orthorhombic. Cleavage: often in groups of platy or tabular crystals. Color: usually white, but may be light shades of blue, brown, yellow, or red. Hardness: 3.0 to 3.5. Streak: white. Luster: vitreous to pearly. Specific gravity: 4.5. Tenacity: brittle. Uses: in heavy muds in oil-well drilling, to increase brilliance in the glass-making industry, as filler for paper, cosmetics, textiles, linoleum, rubber goods, paints. Barite generally occurs in a white massive variety (often appearing earthy when weathered), although some clear to bluish, bladed barite crystals have been observed in several vein deposits in central Kentucky, and commonly occurs as a solid solution series with celestite where barium and strontium can substitute for each other. Various nodular zones have been observed in Silurian–Devonian rocks in east-central Kentucky.
    [Show full text]
  • Petrology, Mineralogy, and Geochemistry Northern California
    Petrology, Mineralogy, and Geochemistry of the Lower Coon Mountain Pluton, Northern California, with Respect to the Di.stribution of Platinum-Group Elements Petrology, Mineralogy, and Geochemistry of the Lower Coon Mountain Pluton, Northern California, with Respect to the Distribution of Platinum-Group Elements By NORMAN J PAGE, FLOYD GRAY, and ANDREW GRISCOM U.S. GEOLOGICAL SURVEY BULLETIN 2014 U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government Text edited by George Havach Illustrations edited by Carol L. Ostergren UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1993 For sale by Book and Open-File Report Sales U.S. Geological Survey Federal Center, Box 25286 Denver, CO 80225 Library of Congress Cataloging in Publication Data Page, Norman J Petrology, mineralogy, and geochemistry of the Lower Coon Mountain pluton, northern California, with respect to the distribution of platinum-group elements I by Norman J Page, Floyd Gray, and Andrew Griscom. p. em.- (U.S. Geological Survey bulletin ; 2014) Includes bibliographical references. 1. Rocks, Igneous-California-Del Norte County. 2. Geochemistry­ California-Del Norte County. I. Gray, Floyd. II. Griscom, Andrew. Ill. Title. IV. Series. QE75.89 no. 2014 [QE461] 557.3 s-dc20 92-27975 [552'.3'0979411] CIP CONTENTS Abstract 1 Introduction 2 Regional geologic setting 2 Geology 2 Shape, size,
    [Show full text]
  • Barite (Barium)
    Barite (Barium) Chapter D of Critical Mineral Resources of the United States—Economic and Environmental Geology and Prospects for Future Supply Professional Paper 1802–D U.S. Department of the Interior U.S. Geological Survey Periodic Table of Elements 1A 8A 1 2 hydrogen helium 1.008 2A 3A 4A 5A 6A 7A 4.003 3 4 5 6 7 8 9 10 lithium beryllium boron carbon nitrogen oxygen fluorine neon 6.94 9.012 10.81 12.01 14.01 16.00 19.00 20.18 11 12 13 14 15 16 17 18 sodium magnesium aluminum silicon phosphorus sulfur chlorine argon 22.99 24.31 3B 4B 5B 6B 7B 8B 11B 12B 26.98 28.09 30.97 32.06 35.45 39.95 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton 39.10 40.08 44.96 47.88 50.94 52.00 54.94 55.85 58.93 58.69 63.55 65.39 69.72 72.64 74.92 78.96 79.90 83.79 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon 85.47 87.62 88.91 91.22 92.91 95.96 (98) 101.1 102.9 106.4 107.9 112.4 114.8 118.7 121.8 127.6 126.9 131.3 55 56 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 cesium barium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon 132.9 137.3 178.5 180.9 183.9 186.2 190.2 192.2 195.1 197.0 200.5 204.4 207.2 209.0 (209) (210)(222) 87 88 104 105 106 107 108 109 110 111 112 113 114 115 116
    [Show full text]
  • Selective Flotation of Witherite from Calcite Using Potassium Chromate As a Depressant
    Physicochem. Probl. Miner. Process., 55(2), 2019, 565-574 Physicochemical Problems of Mineral Processing ISSN 1643-1049 http://www.journalssystem.com/ppmp © Wroclaw University of Science and Technology Received May 31, 2018; reviewed; accepted September 2, 2018 Selective flotation of witherite from calcite using potassium chromate as a depressant Yangshuai Qiu 1, Lingyan Zhang 1,2, Xuan Jiao 1, Junfang Guan 1,2, Ye Li 1,2, Yupeng Qian 1,2 1 School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China 2 Hubei Key Laboratory of Mineral Resources Processing & Environment, Wuhan 430070, China Corresponding author: [email protected] (Lingyan Zhang) Abstract: Witherite has been widely used as an industrial and environmental source of barium, with calcite being the primary associated carbonate mineral. However, few studies have been conducted to effectively concentrate witherite from barium ores. In this work, with the treatment of potassium chromate (K2CrO4) and sodium oleate (NaOL), witherite was selectively separated from calcite through selective flotation at different pH conditions. In addition, contact angle, Zeta potential, adsorption and X-ray photoelectron spectroscopy measurements were performed to characterize the separation mechanisms. The results demonstrated that NaOL had a strong collecting ability for both witherite and calcite; nevertheless, witherite could be effectively selected from calcite with the highest recovery at pH 9 in the presence of K2CrO4. From the XPS measurements, NaOL and K2CrO4 were found to be primarily attached to the surfaces of witherite and calcite through chemisorption. The presence of K2CrO4 on the surface of calcite adversely influenced the NaOL adsorption, which could make the flotation separation efficient and successful.
    [Show full text]
  • Conservation of Coated and Specialty Papers
    RELACT HISTORY, TECHNOLOGY, AND TREATMENT OF SPECIALTY PAPERS FOUND IN ARCHIVES, LIBRARIES AND MUSEUMS: TRACING AND PIGMENT-COATED PAPERS By Dianne van der Reyden (Revised from the following publications: Pigment-coated papers I & II: history and technology / van der Reyden, Dianne; Mosier, Erika; Baker, Mary , In: Triennial meeting (10th), Washington, DC, 22-27 August 1993: preprints / Paris: ICOM , 1993, and Effects of aging and solvent treatments on some properties of contemporary tracing papers / van der Reyden, Dianne; Hofmann, Christa; Baker, Mary, In: Journal of the American Institute for Conservation, 1993) ABSTRACT Museums, libraries, and archives contain large collections of pigment-coated and tracing papers. These papers are produced by specially formulated compositions and manufacturing procedures that make them particularly vulnerable to damage as well as reactive to solvents used in conservation treatments. In order to evaluate the effects of solvents on such papers, several research projects were designed to consider the variables of paper composition, properties, and aging, as well as type of solvent and technique of solvent application. This paper summarizes findings for materials characterization, degradative effects of aging, and some effects of solvents used for stain reduction, and humidification and flattening, of pigment-coated and modern tracing papers. Pigment-coated papers have been used, virtually since the beginning of papermaking history, for their special properties of gloss and brightness. These properties, however, may render coated papers more susceptible to certain types of damage (surface marring, embedded grime, and stains) and more reactive to certain conservation treatments. Several research projects have been undertaken to characterize paper coating compositions (by SEM/EDS and FTIR) and appearance properties (by SEM imaging of surface structure and quantitative measurements of color and gloss) in order to evaluate changes that might occur following application of solvents used in conservation treatments.
    [Show full text]
  • Single Crystal Growth for Topology and Beyond Chandra Shekhar#, Horst Borrmann, Claudia Felser, Guido Kreiner, Kaustuv Manna, Marcus Schmidt, and Vicky Sü
    CHEMICAL METALS SCIENCE & SOLID STATE CHEMISTRY Single crystal growth for topology and beyond Chandra Shekhar#, Horst Borrmann, Claudia Felser, Guido Kreiner, Kaustuv Manna, Marcus Schmidt, and Vicky Sü Single crystals are the pillars for many technological advancements, which begin with acquiring the material. Since different compounds have different physical and chemical properties, different techniques are needed to obtain their single crystals. New classes of quantum materials, from insulators to semimetals, that exhibit non-trivial topologies, have been found. They display a plethora of novel phenomena, including topological surface states, new fermions such as Weyl, Dirac, or Majorana, and non-collinear spin textures such as antiskyrmions. To obtain the crystals and explore the properties of these families of compounds, it is necessary to employ different crystal growth techniques such as the chemical vapour transport method, Bridgman technique, flux growth method, and floating-zone method. For the last four years, we have grown more than 150 compounds in single crystal form by employing these methods. We sometimes go beyond these techniques if the phase diagram of a particular material allows it; e.g., we choose the Bridgman technique as a flux growth method. Before measuring the properties, we fully characterize the grown crystals using different characterization tools. Our TaAs family of crystals have, for the first time, been proven experimentally to exhibit Weyl semimetal properties. They exhibit extremely high magnetoresistance and mobility of charge carriers, which is indicative of the Weyl fermion properties. Moreover, a very large value of intrinsic anomalous Hall and Weyl physics with broken time-reversal symmetry is found in the full-Heuslers, while the half-Heuslers exhibit topological surface states.
    [Show full text]
  • Where Do New Materials Come From? Neither the Stork Nor the Birds and the Bees! in Search of the Next “First Material” Gregory Morrison, Dileka Abeysinghe, Justin B
    2016 Governor’s Award for Excellence in Science Where Do New Materials Come From? Neither the Stork nor the Birds and the Bees! In Search of the Next “First Material” Gregory Morrison, Dileka Abeysinghe, Justin B. Felder, Shani Egodawatte, Timothy Ferreira, Hans-Conrad zur Loye* Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA Materials discovery and optimization has driven the rapid technological advancements that have been observed in our lifetimes. For this advancement to continue, solid-state chemists must continue to develop new materials. Where do these new materials come from? In this review, we discuss the approaches used by the zur Loye group to discover the next “First Material”, a new material exhibiting a desired or not previously observed property that can be optimized for use in the technologies of tomorrow. Specifically, we discuss several crystal growth techniques that we have used with great success to synthesize new materials: the flux growth method, the hydroflux method, and the mild-hydrothermal method. materials, the ever-shrinking cell phone due to improved INTRODUCTION microwave dielectric materials, the enhancement in lithium battery storage capacity due to new intercalation materials, and the improved capacitor due to new ferroelectric materials are all In our complex lives of the 21st Century we rely on technology and excellent examples of materials that were developed only recently. technological devices that work because they contain advanced We should not for one second believe, however, that these materials that exhibit specific properties to perform specific materials were discovered and used without further optimization, functions.
    [Show full text]
  • List of Abbreviations
    List of Abbreviations Ab albite Cbz chabazite Fa fayalite Acm acmite Cc chalcocite Fac ferroactinolite Act actinolite Ccl chrysocolla Fcp ferrocarpholite Adr andradite Ccn cancrinite Fed ferroedenite Agt aegirine-augite Ccp chalcopyrite Flt fluorite Ak akermanite Cel celadonite Fo forsterite Alm almandine Cen clinoenstatite Fpa ferropargasite Aln allanite Cfs clinoferrosilite Fs ferrosilite ( ortho) Als aluminosilicate Chl chlorite Fst fassite Am amphibole Chn chondrodite Fts ferrotscher- An anorthite Chr chromite makite And andalusite Chu clinohumite Gbs gibbsite Anh anhydrite Cld chloritoid Ged gedrite Ank ankerite Cls celestite Gh gehlenite Anl analcite Cp carpholite Gln glaucophane Ann annite Cpx Ca clinopyroxene Glt glauconite Ant anatase Crd cordierite Gn galena Ap apatite ern carnegieite Gp gypsum Apo apophyllite Crn corundum Gr graphite Apy arsenopyrite Crs cristroballite Grs grossular Arf arfvedsonite Cs coesite Grt garnet Arg aragonite Cst cassiterite Gru grunerite Atg antigorite Ctl chrysotile Gt goethite Ath anthophyllite Cum cummingtonite Hbl hornblende Aug augite Cv covellite He hercynite Ax axinite Czo clinozoisite Hd hedenbergite Bhm boehmite Dg diginite Hem hematite Bn bornite Di diopside Hl halite Brc brucite Dia diamond Hs hastingsite Brk brookite Dol dolomite Hu humite Brl beryl Drv dravite Hul heulandite Brt barite Dsp diaspore Hyn haiiyne Bst bustamite Eck eckermannite Ill illite Bt biotite Ed edenite Ilm ilmenite Cal calcite Elb elbaite Jd jadeite Cam Ca clinoamphi- En enstatite ( ortho) Jh johannsenite bole Ep epidote
    [Show full text]
  • Crystallization Processes and Solubility of Columbite-(Mn), Tantalite-(Mn), Microlite, Pyrochlore, Wodginite and Titanowodginite in Highly Fluxed Haplogranitic Melts
    Western University Scholarship@Western Scholarship@Western Electronic Thesis and Dissertation Repository 3-12-2018 10:30 AM Crystallization processes and solubility of columbite-(Mn), tantalite-(Mn), microlite, pyrochlore, wodginite and titanowodginite in highly fluxed haplogranitic melts Alysha G. McNeil The University of Western Ontario Supervisor Linnen, Robert L. The University of Western Ontario Co-Supervisor Flemming, Roberta L. The University of Western Ontario Graduate Program in Geology A thesis submitted in partial fulfillment of the equirr ements for the degree in Doctor of Philosophy © Alysha G. McNeil 2018 Follow this and additional works at: https://ir.lib.uwo.ca/etd Part of the Earth Sciences Commons Recommended Citation McNeil, Alysha G., "Crystallization processes and solubility of columbite-(Mn), tantalite-(Mn), microlite, pyrochlore, wodginite and titanowodginite in highly fluxed haplogranitic melts" (2018). Electronic Thesis and Dissertation Repository. 5261. https://ir.lib.uwo.ca/etd/5261 This Dissertation/Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. Abstract Niobium and tantalum are critical metals that are necessary for many modern technologies such as smartphones, computers, cars, etc. Ore minerals of niobium and tantalum are typically associated with pegmatites and include columbite, tantalite, wodginite, titanowodginite, microlite and pyrochlore. Solubility and crystallization mechanisms of columbite-(Mn) and tantalite-(Mn) have been extensively studied in haplogranitic melts, with little research into other ore minerals. A new method of synthesis has been developed enabling synthesis of columbite-(Mn), tantalite-(Mn), hafnon, zircon, and titanowodginite for use in experiments at temperatures ≤ 850 °C and 200 MPa, conditions attainable by cold seal pressure vessels.
    [Show full text]
  • Compilation of Crystal Growers and Crystal Growth Projects Research Materials Information Center
    ' iW it( 1 ' ; cfrv-'V-'T-'X;^ » I V' 1l1 II V/ f ,! T-'* «( V'^/ l "3 ' lyJ I »t ; I« H1 V't fl"j I» I r^fS' ^SllMS^W'/r V '^Wl/ '/-D I'ril £! ^ - ' lU.S„AT(yMIC-ENERGY COMMISSION , : * W ! . 1 I i ! / " n \ V •i" "4! ) U vl'i < > •^ni,' 4 Uo I 1 \ , J* > ' . , ' ^ * >- ' y. V * / 1 \ ' ' i S •>« \ % 3"*V A, 'M . •. X * ^ «W \ 4 N / . I < - Vl * b >, 4 f » ' ->" ' , \ .. _../.. ~... / -" ' - • «.'_ " . Ife .. -' < p / Jd <2- ORNL-RMIC-12 THIS DOCUMENT CONFIRMED AS UNCLASSIFIED DIVISION OF CLASSIFICATION COMPILATION OF CRYSTAL GROWERS AND CRYSTAL GROWTH PROJECTS RESEARCH MATERIALS INFORMATION CENTER \i J>*\,skJ if Printed in the United States of America. Available from National Technical Information Service U.S. Department of Commerce 5285 Port Royal Road, Springfield, Virginia 22t51 Price: Printed Copy $3.00; Microfiche $0.95 This report was prepared as an account of work sponsored by the United States Government. Neither the United States nor the United States Atomic Energy Commission, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any information, apparatus, product or process disclosed, or represents that its use would not infringe privately owned rights. ORNL-RMIC-12 UC-25 - Metals, Ceramics, and Materials Contract No. W-7405-eng-26 COMPILATION OF CRYSTAL GROWERS AND CRYSTAL GROWTH PROJECTS T. F. Connolly Research Materials Information Center Solid State Division NOTICE This report was prepared as an account of work sponsored by the Unitsd States Government.
    [Show full text]
  • Barite–Celestine Geochemistry and Environments of Formation Jeffrey S
    Barite–Celestine Geochemistry and Environments of Formation Jeffrey S. Hanor Department of Geology and Geophysics Louisiana State University Baton Rouge, Louisiana 70803 INTRODUCTION Minerals in the barite (BaSO4)–celestine (SrSO4) solid solution series, (Ba,Sr)SO4, occur in a remarkably diverse range of sedimentary, metamorphic, and igneous geological environments which span geological time from the Early Archean (~3.5 Ga) to the present. The purpose of this chapter is to review: (1) the controls on the chemical and isotopic composition of barite and celestine and (2) the geological environments in which these minerals form. Some health risks are associated with barite, and these are discussed near the end of this chapter. Although complete solid solution exists between BaSO4 and SrSO4 most representa- tives of the series are either distinctly Ba-rich or Sr-rich. Hence, it is convenient to use the term barite to refer to not only the stochiometric BaSO4 endmember but also to those (Ba,Sr)SO4 solid solutions dominated by Ba. Similarly, the term celestine will refer here not only to the stoichiometric SrSO4 endmember but to solid solutions dominated by Sr. Such usage is in accord with standard mineral nomenclature. The Committee on Mineral Names and Nomenclature of the International Mineralogical Association recognizes “celestine” as the official name for SrSO4. However, the name “celestite” is still commonly used in the literature. Geological significance of barite and celestine Most of the barite which exists in the Earth’s crust has formed through the mixing of fluids, one containing Ba leached from silicate minerals, and the other an oxidized shallow fluid, such as seawater, which contains sulfate.
    [Show full text]
  • Definition of a Mineral Each Mineral Species Has Unique and Identifiable Physical Properties. Form and Habit Terms (Crystal Grow
    Definition of a Mineral • A mineral is a naturally occurring, • homogeneous solid with a Physical Properties of Minerals • definite, but not fixed, composition, and Color, shape, density, • an ordered atomic arrangement that is hardness, etc • formed by inorganic processes. • A mineral is a natural, crystalline phase. Form and Habit Terms Each mineral species has (Crystal Growth Forms) unique and identifiable • Prismatic (well developed prism physical properties. faces) (Pyramidal) • Form and habit (Shape) • Columnar (Irregular prism faces) • Luster • Acicular (needle-like) • Color and Streak • Botryoidal (rounded growth surface) • Cleavage and Fracture • Tabular (Platey) • Hardness • Stellate (Radiating) • Density • Fibrous (fibers, asbestiform) • Tenacity • Dendritic (tree-like) Acicular Fibrous 1 Dendritic Dendritic Radiating Radiating Bladed Botryoidal 2 Prismatic Luster and Transparency • Luster • Transparency – Metallic – Opaque – Resinous – Translucent (waxy) – Transparent – Pearly – Greasy – Adamantine – Vitreous Metallic Adamantine Color and Streak • The reflectance color of minerals is strongly affected by transition metals (V, Cr, Mn, Fe, Co, Ni, and Cu). (Also rare earths) Vitreous Pearly • Color in hand specimen may not be diagnostic. • Color in streak generally indicates presence of iron or other transition metals. Chatoyance, Asterism, Asterism: Star Sapphire and Luminescence • Chatoyance and asterism are optical effects due to diffraction of light from small inclusions. • Luminescence is emission of light. – Visible or UV (black light) – Tribo-luminescence: glow when rubbed – Cathodo-luminescence is emission of light from electron bombardment 3 Cleavage and Fracture Hardness What scratches what? • Crystals tend to break on planes of • 1. Talc 6. Orthoclase weakness. • 2. Gypsum 7. Quartz – Cleavage: perfect – Parting: irregular • 3. Calcite 8. Topaz – Hackly: very irregular • 4. Fluorite 9.
    [Show full text]