Conserve O Gram Volume 11 Issue 10: Radioactive Minerals
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Crystal Chemistry of the Monazite and Xenotime Structures Yuxxnnc Nr
American Mineralogist, Volume 80, pages2I-26, 1995 Crystal chemistry of the monazite and xenotime structures YuxxnNc Nr, JonN M. Hucnns Department of Geology, Miami University, Oxford, Ohio 45056' U.S.A. ANrrrotvv N. M.q'nr,lNo 48 PageBrook Road, Carlisle, Massachusetts01741' U.S.A. Arsrnlcr Monazite and xenotime, the RE(PO,) dimorphs, are the most ubiquitous rare earth (RE) minerals, yet accuratestructure studiesof the natural phaseshave not been reported. Here we report the results of high-precision structure studies of both the natural phasesand the synthetic RE(PO4)phases for all individual stable rare earth elements. Monazite is monoclinic, P2r/n, and xenotime is isostructural with zircon (spacegroup 14r/amd)- Both atomic arrangementsare basedon [001] chains of intervening phosphate tetrahedra and RE polyhedra, with a REO, polyhedron in xenotime that accommodates the heavy lanthanides(Tb-Lu in the synthetic phases)and a REO, polyhedron in monazite that preferentially incorporatesthe larger light rare earth elements(Ia-Gd). As the struc- ture "transforms" from xenotime to monazite, the crystallographic properties are com- parable along the [001] chains, with structural adjustments to the different sizes of RE atoms occurring principally in (001). There are distinct similarities betweenthe structuresthat are evident when their atomic arrangementsare projected down [001]. In that projection, the chains exist i! (100) planes, with two planes per unit cell. In monazite the planes are offset by 2.2 A along [010], relative to those in xenotime, in order to accommodate the larger light RE atoms. The shift of the planes in monazite allows the RE atom in that phaseto bond to an additional 02' atom to complete the REO' polyhedron. -
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 -
The Stability of Lead Isotopes from Thorium
MAY 24, I9I7] NATURE ---------------------------------------------------------245 but I Prof. Stefan lYle:yer may be I .have pointed out the unsuitability of makmg some exammatwn of the radiations of the thonum mmerals for age determination or correlation material, and the results he obtains will therefore be and this is particularly so i.n the case of minerals of very great value in deciding this point. the Palreozoic igneous rocks of Langesundfjord, Nor FREDERICK SoDDY. way. Mr. Lawson and myself based our former con Aberdeen, May 14. that lead could not be the end product of thonum largely on analyses of these minerals. How . PRO.F. SoDDY. having given me the privilege of read e:ver, I have recalculated the ratiQs on the assump mg h1s letter m advance, I should like to take the twn that thonum has one-seventh the lead-producing opportunity of directing attention to the geological age power of uranium, and it is satisfactory to find that :>f the thorium minerals of Ceylon, and to a few further when thorium is less than five times a·s abundant statistics bearing on the suggestion that only 35 per uranium, the ratios agree as closely on th'ts calculation cent. of thorium produces a stable isotope of lead. as do the simple lead-ratios. When thorium is more than five times as abundant as uranium neither set I a!ll to my friend, Mr. E. J. Wayland, late of ratios gives any approach to agreement although of Ceylon, for the follow mg prov1s1onal classdicat10n (in order of age) of the the minerals from anv one locality agree am'ong them older rocks of the island :- selves. -
NEW MINERALS It Is Proposed Hereafter to Indicate In.A General Way the Classification of All New Minerals Recoided in This Department
JOURNAL MINERALOGICAL SOCIETY OF AMENICA 63 Dr. Kunz then spoke of the various city localities and the minerals found therein. He stated that the East Side, from 37 to 110 St., probably afforded the most specimens. The various tunnels and their minerals were spoken of. Capt. Miller called attention to the fine collection of Brooklyn Drift Minerals and Rocks in the collection of the Long Island Historical Society. Ife abo mentioned the occurrence of monazite and xenotime crystals, on the Speedway,Harlem River. Dr. Kunz emphasizedthe irnportance of complete records being kept of all finds. Tnou,q,s L Mrr,r,nn, SecretaryPro, Tem. NEW MINERALS It is proposed hereafter to indicate in.a general way the classification of all new minerals recoided in this department. Subdivision will be first into "families," of which nine may be recognized,as listed in the January number (Am. Min.6 (1), 12,1921). Eachfamilywillbe separatedinto "subfamilies " based on special features of composition. This arrangement is tentative and open to modification, and criticism of it will be welcome, [Eo.] FAMILY 2. SULFIDES, ETC. SosreMrr,v 3. Doust,u suLFrDEs oF METALSAND sEMr-METAr,s. I'LTRABASITE V. Rosrcxf and J. Srnnse-Btinu. Ultrabasit, ein neues Mineral aus Freiberg in Sachsen. (Ultrabasite, a new mineral from Freiberg, Saxony). Rozpr.Eeslcd Ako,il. Prag,25, No. 45, 1916;Z. Krgst. Min., 55,43H39, 1920, Neun: From its extremely basic chemical composition. Pnrsrcar, Pnopnnrrus Color black, somewhat grayish; luster metallic; streak black; cleavage none; fracture scaly, with somewhat greasy luster on the surface. H. : 5; sp. gr. -
Monazite, Rhabdophane, Xenotime & Churchite
Monazite, rhabdophane, xenotime & churchite: Vibrational spectroscopy of gadolinium phosphate polymorphs Nicolas Clavier, Adel Mesbah, Stephanie Szenknect, N. Dacheux To cite this version: Nicolas Clavier, Adel Mesbah, Stephanie Szenknect, N. Dacheux. Monazite, rhabdophane, xenotime & churchite: Vibrational spectroscopy of gadolinium phosphate polymorphs. Spec- trochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Elsevier, 2018, 205, pp.85-94. 10.1016/j.saa.2018.07.016. hal-02045615 HAL Id: hal-02045615 https://hal.archives-ouvertes.fr/hal-02045615 Submitted on 26 Feb 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Monazite, rhabdophane, xenotime & churchite : vibrational spectroscopy of gadolinium phosphate polymorphs N. Clavier 1,*, A. Mesbah 1, S. Szenknect 1, N. Dacheux 1 1 ICSM, CEA, CNRS, ENSCM, Univ Montpellier, Site de Marcoule, BP 17171, 30207 Bagnols/Cèze cedex, France * Corresponding author: Dr. Nicolas CLAVIER ICSM, CEA, CNRS, ENSCM, Univ Montpellier Site de Marcoule BP 17171 30207 Bagnols sur Cèze France Phone : + 33 4 66 33 92 08 Fax : + 33 4 66 79 76 11 [email protected] - 1 - Abstract : Rare-earth phosphates with the general formula REEPO4·nH2O belong to four distinct structural types: monazite, rhabdophane, churchite, and xenotime. -
Mineral Collecting Sites in North Carolina by W
.'.' .., Mineral Collecting Sites in North Carolina By W. F. Wilson and B. J. McKenzie RUTILE GUMMITE IN GARNET RUBY CORUNDUM GOLD TORBERNITE GARNET IN MICA ANATASE RUTILE AJTUNITE AND TORBERNITE THULITE AND PYRITE MONAZITE EMERALD CUPRITE SMOKY QUARTZ ZIRCON TORBERNITE ~/ UBRAR'l USE ONLV ,~O NOT REMOVE. fROM LIBRARY N. C. GEOLOGICAL SUHVEY Information Circular 24 Mineral Collecting Sites in North Carolina By W. F. Wilson and B. J. McKenzie Raleigh 1978 Second Printing 1980. Additional copies of this publication may be obtained from: North CarOlina Department of Natural Resources and Community Development Geological Survey Section P. O. Box 27687 ~ Raleigh. N. C. 27611 1823 --~- GEOLOGICAL SURVEY SECTION The Geological Survey Section shall, by law"...make such exami nation, survey, and mapping of the geology, mineralogy, and topo graphy of the state, including their industrial and economic utilization as it may consider necessary." In carrying out its duties under this law, the section promotes the wise conservation and use of mineral resources by industry, commerce, agriculture, and other governmental agencies for the general welfare of the citizens of North Carolina. The Section conducts a number of basic and applied research projects in environmental resource planning, mineral resource explora tion, mineral statistics, and systematic geologic mapping. Services constitute a major portion ofthe Sections's activities and include identi fying rock and mineral samples submitted by the citizens of the state and providing consulting services and specially prepared reports to other agencies that require geological information. The Geological Survey Section publishes results of research in a series of Bulletins, Economic Papers, Information Circulars, Educa tional Series, Geologic Maps, and Special Publications. -
Stillwellite-(Ce) (Ce, La, Ca)Bsio
Stillwellite-(Ce) (Ce; La; Ca)BSiO5 c 2001 Mineral Data Publishing, version 1.2 ° Crystal Data: Hexagonal. Point Group: 3: As °at rhombohedral crystals, to 4 cm, and massive. Twinning: Observed about [100]. Physical Properties: Cleavage: One imperfect. Fracture: Conchoidal. Hardness = 6.5 D(meas.) = 4.57{4.60 D(calc.) = 4.67 » Optical Properties: Transparent to translucent. Color: Red-brown to pale pink; colorless in thin section. Streak: White. Optical Class: Uniaxial (+) to biaxial (+). ! = 1.765{1.784 ² = 1.780{1.787 2V(meas.) = 0±{6± Cell Data: Space Group: P 31: a = 6.841{6.844 c = 6.700{6.702 Z = 3 X-ray Powder Pattern: Mary Kathleen mine, Australia. 3.43 (s), 2.96 (s), 2.13 (ms), 4.44 (m), 1.864 (m), 2.71 (mw), 2.24 (mw) Chemistry: (1) (2) (1) (2) (1) (2) SiO2 22.40 22.06 La2O3 27.95 19.12 MgO 0.06 UO2 0.22 Ce2O3 33.15 30.82 CaO 0.95 0.34 ThO2 5.41 Pr2O3 1.82 F 0.30 + B2O3 12.23 [13.46] Nd2O3 5.36 H2O 0.85 Al2O3 0.42 Sm2O3 0.34 H2O¡ 0.10 Y2O3 0.74 0.28 Fe2O3 0.18 P2O5 0.67 Total [100.00] [99.26] (1) Mary Kathleen mine, Australia; recalculated to 100.00% after removal of very small amounts of uraninite and apatite determined by separate analysis. (2) Vico volcano, near Vetralla, Italy; by electron microprobe, B2O3 calculated from stoichiometry, original total given as 99.23%; corresponds to (Ce0:50La0:31Nd0:08Th0:05Pr0:03Ca0:02Sm0:01)§=1:00B1:02Si0:97O5: Occurrence: Locally abundant as a metasomatic replacement of metamorphosed calcareous sediments (Mary Kathleen mine, Australia); in alkalic pegmatites in syenite in an alkalic massif (Dara-i-Pioz massif, Tajikistan). -
Roscherite-Group Minerals from Brazil
■ ■ Roscherite-Group Minerals yÜÉÅ UÜté|Ä Daniel Atencio* and José M.V. Coutinho Instituto de Geociências, Universidade de São Paulo, Rua do Lago, 562, 05508-080 – São Paulo, SP, Brazil. *e-mail: [email protected] Luiz A.D. Menezes Filho Rua Esmeralda, 534 – Prado, 30410-080 - Belo Horizonte, MG, Brazil. INTRODUCTION The three currently recognized members of the roscherite group are roscherite (Mn2+ analog), zanazziite (Mg analog), and greifensteinite (Fe2+ analog). These three species are monoclinic but triclinic variations have also been described (Fanfani et al. 1977, Leavens et al. 1990). Previously reported Brazilian occurrences of roscherite-group minerals include the Sapucaia mine, Lavra do Ênio, Alto Serra Branca, the Córrego Frio pegmatite, the Lavra da Ilha pegmatite, and the Pirineus mine. We report here the following three additional occurrences: the Pomarolli farm, Lavra do Telírio, and São Geraldo do Baixio. We also note the existence of a fourth member of the group, an as-yet undescribed monoclinic Fe3+-dominant species with higher refractive indices. The formulas are as follows, including a possible formula for the new species: Roscherite Ca2Mn5Be4(PO4)6(OH)4 • 6H2O Zanazziite Ca2Mg5Be4(PO4)6(OH)4 • 6H2O 2+ Greifensteinite Ca2Fe 5Be4(PO4)6(OH)4 • 6H2O 3+ 3+ Fe -dominant Ca2Fe 3.33Be4(PO4)6(OH)4 • 6H2O ■ 1 ■ Axis, Volume 1, Number 6 (2005) www.MineralogicalRecord.com ■ ■ THE OCCURRENCES Alto Serra Branca, Pedra Lavrada, Paraíba Unanalyzed “roscherite” was reported by Farias and Silva (1986) from the Alto Serra Branca granite pegmatite, 11 km southwest of Pedra Lavrada, Paraíba state, associated with several other phosphates including triphylite, lithiophilite, amblygonite, tavorite, zwieselite, rockbridgeite, huréaulite, phosphosiderite, variscite, cyrilovite and mitridatite. -
Life Cycle Assessment of Separation Methods of Cerium Oxide
907 A publication of CHEMICAL ENGINEERING TRANSACTIONS VOL. 74, 2019 The Italian Association of Chemical Engineering Online at www.cetjournal.it Guest Editors: Sauro Pierucci, Jiří Jaromír Klemeš, Laura Piazza Copyright © 2019, AIDIC Servizi S.r.l. ISBN 978-88-95608-71-6; ISSN 2283-9216 DOI: 10.3303/CET1974152 Life Cycle Assessment of Separation Methods of Cerium Oxide from Monazite Ore a b Dussadee. Ratthanapra , Unchalee. Suwanmanee* aResearch and Development Division, Thailand Institute and Nuclear Technology, Nakhon Nayok 26120, Thailand. b Department of Chemical Engineering, Faculty of Engineering, Srinakharinwirot University, Nakhon Nayok 26120, Thailand. [email protected] Life cycle assessment was applied to evaluate the environmental impact of cerium oxide (CeO2) production systems from monazite ore using integrating and excluding liquid-liquid extraction methods. It is a heterogeneous rare earths oxides catalyst which can be utilized for catalysed transesterification to produce biodiesel. The impact assessment methodology used for characterization was the midpoint CML baseline method in terms the potentials of abiotic depletion, global warming, ozone layer depletion, human toxicity, freshwater aquatic ecotoxicity, marine aquatic ecotoxicity, terrestrial ecotoxicity, photochemical oxidation, acidification, and eutrophication. The Eco-indicator 99 method was performed an endpoint approach: human health, ecosystem quality, and resources. The data on process was available from a field study conducted in Thailand Institute of Nuclear Technology and applied into SimaPro 8.2.5. The LCA results showed that the removal of solvent extraction process can achievable the higher purity of CeO2 concentration and presented the most attractive process for cerium oxide from monazite ore in term of environmental impact assessment. -
Production of Rare Earth Elements from Malaysian Monazite by Selective Precipitation
Malaysian Journal of Analytical Sciences, Vol 20 No 1 (2016): 44 - 50 MALAYSIAN JOURNAL OF ANALYTICAL SCIENCES ISSN 1394 - 2506 Published by The Malaysian Analytical Sciences Society PRODUCTION OF RARE EARTH ELEMENTS FROM MALAYSIAN MONAZITE BY SELECTIVE PRECIPITATION (Penghasilan Unsur Nadir Bumi daripada Mineral Monazit Menggunakan Pemendakan Terpilih) Che Nor Aniza Che Zainul Bahri*, Wadeeah M. Al- Areqi, Amran Ab. Majid, Mohd Izzat Fahmi Mohd Ruf Nuclear Science Program, School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia *Corresponding author: [email protected] Received: 2 November 2015; Accepted: 31 December 2015 Abstract Rare earth elements (REEs) are very valuable and have high demands for advanced technology nowadays. REEs can be classified to light rare earth elements (LREEs) and heavy rare earth elements (HREEs). Malaysian rare earth ore especially monazite, is rich with LREEs compared to HREEs. Therefore a study was carried out to extract the REE from Malaysian monazite. The objectives of this study are to determine the content of REEs in Malaysian monazite leach solution, as well as to produce high grade of REEs. Concentrated sulphuric acid was used in digestion process and the filtrate containing the REEs was determined using Inductively Coupled Plasma- Mass Spectrometry (ICP-MS). Ammonia solution was used for REEs precipitation from monazite leach solution. The result indicated that REEs was successfully separated from monazite leach solution through selective precipitation using ammonia at pH 2.34 and the percentage of REEs that successfully separated was 70.03 – 81.85%. The percentage of REEs which successfully separated from final solution was 96.05 – 99.10%. -
Rethinking Rare Earths Monazite
TSX-V: MDL TSX-V: MDL OTCQX: MLLOF FSE: MRD Issued and Outstanding 44.6 M Rethinking Rare Earths Warrants 9.2 M Medallion is rethinking accepted rare-earth exploration and development strategies under the leadership of veteran geologist and rare-earth expert Dr. Bill Bird. With the accelerated need Options 4.0 M to relaunch the rare-earth exploration and development industry, most company strategies Fully Diluted 57.8 M focused on the portfolio of hard-rock occurrences that were discovered in the mid-20th Century, Market Capitalization approx. $8 M before China’s dominance. Most of these occurrences require complex metallurgy, huge investments for infrastructure and years to get to production. Medallion recognized in 2010 that there was no company or REE-project, with the possible The Medallion strategy, producing rare earths exception of Molycorp’s Mountain Pass Mine, that could solve the most critical REE-supply issues: from heavy-mineral-sands monazite, is a 1. a near-term shortage of rare-earth elements, and great idea. I have worked with mineral-sands 2. a lack of low-production-cost projects. producers for many years and, generally, Over the past two years, solving these issues has been the driving force of Medallion’s they have just discarded their monazite. The exploration and project-acquisition strategy. Rather than focusing on properties with producers are always keen to maximize value complicated, expensive and untested metallurgy, Medallion is pursuing monazite processing partnerships and purchase-agreements. Monazite is a rare-earth phosphate mineral that is from their resources, and Medallion is offering a major source of rare earths. -
Separation of Radioactive Elements from Rare Earth Element-Bearing Minerals
metals Review Separation of Radioactive Elements from Rare Earth Element-Bearing Minerals Adrián Carrillo García 1, Mohammad Latifi 1,2, Ahmadreza Amini 1 and Jamal Chaouki 1,* 1 Process Development Advanced Research Lab (PEARL), Chemical Engineering Department, Ecole Polytechnique de Montreal, C.P. 6079, Succ. Centre-ville, Montreal, QC H3C 3A7, Canada; [email protected] (A.C.G.); mohammad.latifi@polymtl.ca (M.L.); [email protected] (A.A.) 2 NeoCtech Corp., Montreal, QC H3G 2N7, Canada * Correspondence: [email protected] Received: 8 October 2020; Accepted: 13 November 2020; Published: 17 November 2020 Abstract: Rare earth elements (REE), originally found in various low-grade deposits in the form of different minerals, are associated with gangues that have similar physicochemical properties. However, the production of REE is attractive due to their numerous applications in advanced materials and new technologies. The presence of the radioactive elements, thorium and uranium, in the REE deposits, is a production challenge. Their separation is crucial to gaining a product with minimum radioactivity in the downstream processes, and to mitigate the environmental and safety issues. In the present study, different techniques for separation of the radioactive elements from REE are reviewed, including leaching, precipitation, solvent extraction, and ion chromatography. In addition, the waste management of the separated radioactive elements is discussed with a particular conclusion that such a waste stream can be