DOCSLIB.ORG

Download the Scanned

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Download the Scanned American Mineralogist, Volume 59, pages 896-899, 1974 Metavivianite,Fe.(POu),.8HrO, a New Mineral' Cnlnrps Rrrz Department of Chemistry, Entc J. EssnNn,,c,Nu DoNlr,D R. PEAcoR Department of Geology and Mineralogy, The Uniaersity of Michigan, Ann Arbor, Michigan 48104 Abstract Metavivianite, Fe*(POn),'8H,O, is a new mineral occurring with kryzhanovskitein solution cavities in triphylite at the Big Chief pegmatite near Glendale, South Dakota. It is triclinic, - - - with a 7.814, b 9.084., c 4.65A, a - 94.77",F - 97.15",r - 107.37",and is isostructural with symplesite, Fe"(AsO.),.EH,O. Electron probe analysis indicates that it is a polymorph of vivianite. Vivianite and parasymplesite are therefore isostructural, monoclinic dimorphs cif the isoetructural and triclinic minerals metavivianite and symplesite. fntroduction the two phosphatesand the two arsenates.Type The pegmatitesof the Black Hills, South Dakota, material of metavivianite is present in the collec- are well known as sourcesof a variety of primary tions of the U. S. National Museum (Smithsonian and secondaryphosphates. In 1969, Dr. David Institution) and the Department of Geology and Garske of the South Dakota School of Mines kindly Mineralogy, The University of Michigan. The min- donated to us specimens of phosphate minerals eral and the name have been approved by the which are products of the alteration of triphylite. I.M.A. Commissionon New Minerals and Mineral Crystals from one of these specimenswere used Names. in a single-crystal study, with preliminary results Occurrence indicating that they were triclinic, and similar to symplesite,Fes(AsOa)2.8II2O. However, chemical The mineral occurs on one specimen collected analysisindicated the presenceof P but no As. at the Big Chief pegmatitemine, one half mile south Symplesiteis the triclinic dimorph of monoclinic of Glendale, Pennington County, South Dakota parasymplesite.The mineral vivianite, Fes(PO+)2. (43"52.3' N, 103'22.1' W). Phosphatesfrom this SH2O, is isostructuralwith parasymplesite(Mori locality have been describedby Roberts and Rapp ( and Ito, 1950).Our preliminary results thus indi- 1965). Crystalsof primarytriphylite, some measur- catedthat our specimenswere a dimorph of vivian- ing up to 6 feet in diameter, have been altered by ite and related to that mineral as symplesiteis to late-stagepegmatitic solutions. Secondaryminerals parasymplesite.Detailed examinationhas verified are abundant and include ludlamite. hureaulite. this relationship.The name metavivianitehas been beraunite, rockbridgeite, laueite, heterosite-purpu- chosento emphasizethe dimorphousrelationship rite. and strunzite. to vivianite,as with the phosphates(meta)vauxite The metavivianiteoccurs on a specimenof mas- and (meta)strengite.The nature of the existing sive triphylite containing veinlets of spessartine-rich names for the two related arsenatesunfortunately garnet, pyrrhotite, sphalerite, and quartz. The sur- precludesa choice of names which would more face of the triphylite is pitted with solution cavities clearly illustrate the isostructural relations between up to I mm in diameter which generallyfollow the in -;Co"triUution traces of cleavages.The metavivianiteoccurs No. 318 from the Mineralogical Labora- the solution cavities, intimately intergrown with tory, Department of Geology and Mineralogy, The Uni- dark red kryzhanovskite.The identity of the latter versity of Michigan, Ann Arbor, Michigan 48104. mineral was establishedusing single-crystaldiftrac- 896 METAVIVIANITE, A NEW MINERAL E97 tion (a = 8.26A, b : IO.I2 A, c : 9.37A, space TrsrB 1. X-Ray Powder Data for Metavivianite* group Pcnb) and qualitative microprobe analysis, d..1(A) dol"(A) d""t (A) dou" (A) I with comparisonwith the data of Moore (1971). hkl Kryzhanovskiteis the only mineral observedto be 8.60 8.59 40 2tr z.7d 010 t I 30 in an apparent equilibrium relationship with meta- 110 6.73 6.71 100 22), . 11f---2. present 110 4.89 4.46 40 vivianite, although hureaulite is in some 011 4.27 4.27 IO 2OI 2.O I Z.O I 5 ^- other cavities. ^- rl1 z.ovl lll J.OOI 1 af in - -^-z.ol, L0 210 r.ei 310 z. ]91 Physical Properties ll1 3.7r 3.72 2 320 2.49 2.50 10 010 3.64 3.63 2 l2l 2.48 2.48 2 Metavivianite occurs as flat, prismatic crystals, 300 2.45 2.46 2 e ocl r.743 5 elongated,alongc, and with principal form {110}. III t0 2to 3.Q61 1. 631 l0 Somecrystals having more regular cross-sectionsare 1.503 2 (110) r3g 3.01 3.00 5 r.456 l0 striated parallel to c. There is a perfect 021 2.95 2.95 5 1. 341 2 color is leek-green.Most crystals are 12I 2.91 2.90 20 cleavage.The 1. 309 2 opaque to translucent, but small grains are trans- *FeK Mn-filtered radiation. CaDEra radlus 57.3 m. Inlen- parent. The specific gravity was not measureddue sities visully estiMted' Thele are a nutbslr of addirional, to the small size of the crystals and the presence very weak lines qith d-values less than 1.3 A. of impurities.Thb calculateddensity is 2.69 gmfcml. Optical properties bf metavivianite are generally similar to those of Vivianite.By direct measurement, the single-crystal study. One other line not listed 2V" is +. 85 :L 5o. Indices of refraction ore a = in Table 1 with a spacing of 3.47 A appeared on 1.579! 0.006,B = 1.603:L 0.002 andy = 1.629 the photographs. This was not indexable using the i 0.002. The relation between the opticdl ,direc- metavivianite unit cell, but since it varied in in- tionsand cleavage is X I (110), YZ ll (110). The tensity from 2 to 30 on different photographs, and pleochroic formula is X > Z > Y, with X = light- since some impurity was present in all X-rayed blue to blue-green,Y - yellow-greento light green, samples, it is assumed to be due to an impurity. Z - yellow to light green. The pleochroiGcolors As expected for two isostructural compounds, are presumablyintensified by oxidation of the iron, the patterns of symplesite and metavivianite are but the physical properties were measuredon light- similar. The larger interplanar spacings for symple- colored grains. site, relative to corresponding lines for metavivian- ite, result in clear differences between the patterns. CrystallograPhy The patterns for vivianite and metavivianite are also Singlecrystals were studiedusing Weissenbergand similar, as expected from their structural similarity' precessionmethods. Unit-cell parameters are a : The patterns of each have unique features with t.st(z)A, b : 9.08(2)A, . : 4.6s(l)A, o : respect to the first peak at approximately 8 A. 94.77(10)",p : 97.15(10)o,y : 107.37(10)'.The Chemical Analysis spacegroup is Pl or Pi. X-ray photographsshowed the presenceof two twinned lattices. The crystals A specimen of metavivianite and a vivianite from are twinned on {110}. Wolfe (1940) showed that an unknown locality were analyzed using the electron the lattices of the monoclinic members of the vi- microprobe. The results are listed in Table 2. The vianite group (parasymplesitewas not recognizedat metavivianite is very similar to the vivianite, both that time) are closely related to the lattices of the phaseshaving essentiallythe same wt/percent ratios triclinic phases (e.g., symplesite).The twin iilane of Fe/Mn, approximately 10:1. Only traces of metavivianite' {l l0} of the triclinic phasesis structurally equivalent other elements are present in the to the true mirror plane (010) in the monoilinic There is less than 0. I percent As since it was not phases.We have verified this relation by comparing detected using repeated, slow spectrometer scans. photographs of untwinned vivianite and twinned The slightly high totals of wt/percent oxides and metavivianite.Twinning was not observedoptically. cations sums are probably due to oxidation of part Data from an FeKa powder photographare listed of the iron and concomitant loss of some water' in Table 1. Calculated interplanar spacingsand We conclude that metavivianite and the vivianite are indiceswere obtainedusing lattice parametersfrom nearly identical in composition for the elements 898 RITZ, ESSENE, AND PEACOR Tesrn 2. Chemical Analyses The sampleswere imbeddedin KBr pellets.A spec- trum of KBr blank showed no absorption above Wt Percent 400 cm-'. and noticeablelines to absorbed oxides Metavivianlte Vivianlte Fe3(pob)2,gH2O no due HzO. The spectra of vivianite and metavivianite Fe0 38.9 37,1 43,0 MnO 3.5 show broad absorptionsaround the regionsof 3400, Nto 0.13 0.6 Cuo <0,05 0, 14 1600, 90O,and 50Ocm-1. The first two broad peaks Z\O <0.05 indicate the presenceof water, and the last two Ca0 0.5 <0,06 peaks are characteristic of POas-. The qualitative Na2o <0.07 0.8 28.4 28.0 28.3 spectra indicate the similarity in composition and tu.os <0.1 <0.1 Hzo (28.7) (28.7) 24.7 crystal structure of vivianite and metavivianite. suh 100,8 100.9 t00.0 Discussion Cations for 8 orygens (atonic basis) Fe 2,7L 2,63 3.00 Metavivianite and vivianite are members of a Mn 0. 30 0.25 series of hydrated iron phosphates:Fes(PO+)z' Ni 0. 01 0. 04 Cu 0,01 nH2O, which includes phosphoferrite (n : 3), Zt 0.09 ludlamite (n = 4), and anhydrous sarcopside Ca 0.05 Na 0.13 (Moore, l97l).'z All theseminerals show substan- 2.OO L97 2,00 o 8.00 8.00 8.00 tial solid solution with Mn, and are easily oxidized H-0 (8.00) (8.0o) 8,00 to Fest with loss of H-. su The membersof this seriesare related by simple cations 5,06 S .f2 5. 00 *Mlcroplobe reactionswith increasingtemperature: standards used: Fe-Blnns ilnenite, Mn_ Broken HI11 rhodonite, Ni-synthetic NlAl2Or, Cu_Cu'necal, zn-zlncian calclte, Ca-Calclte, Na_AneIia albiCe, p_Black vivianite or Hllls -ludlamite HrO+ phosphoferrite HzO triphylire.
Load more

Recommended publications
  • Kinetics of Phosphorus Release from Vivianite, Hydroxyapatite, and Bone Char Influenced by Organic and Inorganic Compounds
    Article Kinetics of Phosphorus Release from Vivianite, Hydroxyapatite, and Bone Char Influenced by Organic and Inorganic Compounds Elisabeth Schütze, Stella Gypser * and Dirk Freese Faculty of Environment and Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, Chair of Soil Protection and Recultivation, Konrad-Wachsmann-Allee 6, 03046 Cottbus, Germany; [email protected] (E.S.); [email protected] (D.F.) * Correspondence: [email protected] Received: 7 February 2020; Accepted: 12 March 2020; Published: 16 March 2020 Abstract: The availability of P is often insufficient and limited by accumulation in soils. This led to the necessity of solutions for the recovery as well as recycling of secondary P resources. Batch experiments were conducted with CaCl2 and citric acid to characterize P release kinetics from vivianite, hydroxyapatite, and bone char. While the P release during the CaCl2 treatment was so low that only vivianite and hydroxyapatite showed a slightly higher release with increasing CaCl2 concentration, the increase of dissolved P was more pronounced for citric acid. The application of citric acid resulted in a 32,190-fold higher P release for bone char. Fourier-transform infrared spectroscopic data suggested higher instability of hydroxyapatite than for bone char. The kinetic data showed that bone char, especially at a lower particle size, had a higher long-term P release than hydroxyapatite or vivianite. The suitability of hydroxyapatite and bone char as a poorly soluble, but sustainable P source is better than that of vivianite. However, the efficiency as a P fertilizer is also dependent on present soil P mobilization processes.
    [Show full text]
  • 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]
  • L. Jahnsite, Segelerite, and Robertsite, Three New Transition Metal Phosphate Species Ll. Redefinition of Overite, an Lsotype Of
    American Mineralogist, Volume 59, pages 48-59, 1974 l. Jahnsite,Segelerite, and Robertsite,Three New TransitionMetal PhosphateSpecies ll. Redefinitionof Overite,an lsotypeof Segelerite Pnur BnnN Moone Thc Departmcntof the GeophysicalSciences, The Uniuersityof Chicago, Chicago,Illinois 60637 ilt. lsotypyof Robertsite,Mitridatite, and Arseniosiderite Peur BmaN Moonp With Two Chemical Analvsesbv JUN Iro Deryrtrnent of GeologicalSciences, Haraard Uniuersity, Cambridge, Massrchusetts 02 I 38 Abstract Three new species,-jahnsite, segelerite, and robertsite,-occur in moderate abundance as late stage products in corroded triphylite-heterosite-ferrisicklerite-rockbridgeite masses, associated with leucophosphite,hureaulite, collinsite, laueite, etc.Type specimensare from the Tip Top pegmatite, near Custer, South Dakota. Jahnsite, caMn2+Mgr(Hro)aFe3+z(oH)rlPC)oln,a 14.94(2),b 7.14(l), c 9.93(1)A, p 110.16(8)", P2/a, Z : 2, specific gavity 2.71, biaxial (-), 2V large, e 1.640,p 1.658,t l.6lo, occurs abundantly as striated short to long prismatic crystals, nut brown, yellow, yellow-orange to greenish-yellowin color.Formsarec{001},a{100},il2oll, jl2}ll,ft[iol],/tolll,nt110],andz{itt}. Segeierite,CaMg(HrO)rFes+(OH)[POdz, a 14.826{5),b 18.751(4),c7.30(1)A, Pcca, Z : 8, specific gaavity2.67, biaxial (-), 2Ylarge,a 1.618,p 1.6t5, z 1.650,occurs sparingly as striated yellow'green prismaticcrystals, with c[00], r{010}, nlll0l and qll2l } with perfect {010} cleavage'It is the Feg+-analogueofoverite; a restudy on type overite revealsthe spacegroup Pcca and the ideal formula CaMg(HrO)dl(OH)[POr]r. Robertsite,carMna+r(oH)o(Hro){Ponlr, a 17.36,b lg.53,c 11.30A,p 96.0o,A2/a, Z: 8, specific gravity3.l,T,cleavage[l00] good,biaxial(-) a1.775,8 *t - 1.82,2V-8o,pleochroismextreme (Y, Z = deep reddish brown; 17 : pale reddish-pink), @curs as fibrous massesand small wedge- shapedcrystals showing c[001 f , a{1@}, qt031}.
    [Show full text]
  • Vibrational Spectroscopic Characterization of the Phosphate Mineral Ludlamite
    Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 103 (2013) 143–150 Contents lists available at SciVerse ScienceDirect Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy journal homepage: www.elsevier.com/locate/saa Vibrational spectroscopic characterization of the phosphate mineral ludlamite (Fe,Mn,Mg)3(PO4)2Á4H2O – A mineral found in lithium bearing pegmatites ⇑ Ray L. Frost a, , Yunfei Xi a, Ricardo Scholz b, Fernanda M. Belotti c a School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001, Australia b Geology Department, School of Mines, Federal University of Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, MG 35400-00, Brazil c Federal University of Itajubá, Campus Itabira, Itabira, MG 35903-087, Brazil highlights graphical abstract " We have analyzed the phosphate Raman spectrum of ludlamite in the phosphate stretching region. mineral ludlamite by EMP-WDS. " The mineral is a ferrous phosphate with some minor substitution of Mg and Mn. " Spectroscopic analysis shows the mineral is predominantly a phosphate with some minor hydrogen phosphate units. " The position of the OH bands shows that water is very strongly hydrogen bonded in the ludlamite structure. article info abstract Article history: The objective of this work is to analyze ludlamite (Fe,Mn,Mg)3(PO4)2Á4H2O from Boa Vista mine, Galiléia, Available online 16 November 2012 Brazil and to assess the molecular structure of the mineral. The phosphate mineral ludlamite has been characterized by EMP-WDS, Raman and infrared spectroscopic measurements. The mineral is shown to Keywords: be a ferrous phosphate with some minor substitution of Mg and Mn.
    [Show full text]
  • 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
    [Show full text]
  • High-Temperature Thermomagnetic Properties of Vivianite Nodules
    EGU Journal Logos (RGB) Open Access Open Access Open Access Advances in Annales Nonlinear Processes Geosciences Geophysicae in Geophysics Open Access Open Access Natural Hazards Natural Hazards and Earth System and Earth System Sciences Sciences Discussions Open Access Open Access Atmospheric Atmospheric Chemistry Chemistry and Physics and Physics Discussions Open Access Open Access Atmospheric Atmospheric Measurement Measurement Techniques Techniques Discussions Open Access Open Access Biogeosciences Biogeosciences Discussions Open Access Open Access Clim. Past, 9, 433–446, 2013 Climate www.clim-past.net/9/433/2013/ Climate doi:10.5194/cp-9-433-2013 of the Past of the Past © Author(s) 2013. CC Attribution 3.0 License. Discussions Open Access Open Access Earth System Earth System Dynamics Dynamics Discussions High-temperature thermomagnetic properties of Open Access Open Access vivianite nodules, Lake El’gygytgyn, Northeast RussiaGeoscientific Geoscientific Instrumentation Instrumentation P. S. Minyuk1, T. V. Subbotnikova1, L. L. Brown2, and K. J. Murdock2 Methods and Methods and 1North-East Interdisciplinary Scientific Research Institute, Far East Branch of the Russian AcademyData Systems of Sciences, Data Systems Magadan, Russia Discussions Open Access 2 Open Access Department of Geosciences, University of Massachusetts, Amherst, USA Geoscientific Geoscientific Correspondence to: P. S. Minyuk ([email protected]) Model Development Model Development Received: 7 September 2012 – Published in Clim. Past Discuss.: 9 October 2012 Discussions Revised: 15 January 2013 – Accepted: 15 January 2013 – Published: 19 February 2013 Open Access Open Access Hydrology and Hydrology and Abstract. Vivianite, a hydrated iron phosphate, is abun- 1 Introduction Earth System Earth System dant in sediments of Lake El’gygytgyn, located in the Anadyr Mountains of central Chukotka, northeastern Rus- Sciences Sciences sia (67◦300 N, 172◦050 E).
    [Show full text]
  • New Minerals: Doubtful Species Class: Phosphates' Etc
    44 THE AMENCAN MINERALOGIST NEW MINERALS: DOUBTFUL SPECIES CLASS: PHOSPHATES' ETC. Lehnerite F. Miillbauer: Die Phosphatpegmatite von Hagendorf i' Bayern' (The phos- (1925)' phate pegmatites of Hagendorf, Bavaria') Z eit' Kr y st.,61, 331, Naur: Named after the mineral collector Lehner- Cqnurclr. Pnoptnrnis: A hydrous basic phosphate of iron' Formula: TFeO' 2P2Ob.6HzO. Analysis: PzOt 34.20,FeO 46.35 ,MnO 2'95, MgO 2'43, IlzO 14'07' Sum 100. (Analysis after deduction of insoluble material and alumina') Cnvsrltrocneprrcer PnornnrrEs: Monoclinic, prismatic, with forms (001)' (110),(101), (109), (I05), (122),(432). a:b:c:0.8965:r:2'4939' B:110" 23" Pnvsrcar. eNo Oprrcar Pnoplnrres: Color apple green' Biaxial, positive' Plane of the optic axes is parallel to (010). Bxo makes about 28" with the normal to c. Cleavage parallel to the base, perfect. occunnnNcn: In small crystals or grains and veins between triploidite crystals, in apatite, or in cracks in triplite or triphylite at Hagendorf, Bavaria' DrscussroN: This mineral is very near to ludlamite in composition' The optical and crystallographic data, howevet, are not sufficiently detailed to determine with certainty the relation of this mineral to ludlamite. W'F'F' Wentzelite O?. Cit., p.333. N.tue ' Named in honor of Father Hieronymus Wenlzel', discoverer of the Ploystein phosphate locality. Cnnurcer. Couposnrow: A hydrous phosphate of mangbnese' Formula: 3MnO. PeOr. 5HzO. Analysis: PzOs 39.37, FeO, 6'01, MnO 21'13, MgO 6'83' HrO 23.66. (100), Cnvstelr.ocnePErcAr, PRoPERTTES: Monoclinic, prismatic' Forms (001),(110), (T01),(113). a:b:c:2.3239:l:2.8513.
    [Show full text]
  • The Mineralogy and Crystallography of Pyrrhotite
    Chapter 1 INTRODUCTION ________________________________________________________ 1.1 Introduction Pyrrhotite Fe(1-x)S is one of the most commonly occurring metal sulfide minerals and is recognised in a variety of ore deposits including nickel-copper, lead-zinc, and platinum group element (PGE). Since the principal nickel ore mineral, pentlandite, almost ubiquitously occurs coexisting with pyrrhotite, the understanding of the behaviour of pyrrhotite during flotation is of fundamental interest. For many nickel processing operations, pyrrhotite is rejected to the tailings in order to control circuit throughput and concentrate grade and thereby reduce excess sulfur dioxide smelter emissions (e.g. Sudbury; Wells et al., 1997). However, for platinum group element processing operations, pyrrhotite recovery is targeted due to its association with the platinum group elements and minerals (e.g. Merensky Reef; Penberthy and Merkle, 1999; Ballhaus and Sylvester, 2000). Therefore, the ability to be able to manipulate pyrrhotite performance in flotation is of great importance. It can be best achieved if the mineralogical characteristics of the pyrrhotite being processed can be measured and the relationship between mineralogy and flotation performance is understood. The pyrrhotite mineral group is non-stoichiometric and has the generic formula of Fe(1-x)S where 0 ≤ x < 0.125. Pyrrhotite is based on the nickeline (NiAs) structure and is comprised of several superstructures owing to the presence and ordering of vacancies within its structure. Numerous pyrrhotite superstructures have been recognised in the literature, but only three of them are naturally occurring at ambient conditions (Posfai et al., 2000; Fleet, 2006). This includes the stoichiometric FeS known as troilite which is generally found in extraterrestrial localities, but on occasion, has also been recognised in some nickel deposits (e.g.
    [Show full text]
  • 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.
    [Show full text]
  • Strengite.Pdf
    3+ Strengite Fe PO4 • 2H2O c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Orthorhombic. Point Group: 2/m 2/m 2/m. Crystals are variable in habit, may be dominated by {111}, lathlike along [001], or elongated along [100] or [010], to 5 cm, with many forms. Generally radial fibrous, as botryoidal or spherical aggregates and crusts. Twinning: Rarely on {201}. Physical Properties: Cleavage: On {010}, good; on {001}, poor. Hardness = 3.5 D(meas.) = 2.84–2.87 D(calc.) = 2.84 Optical Properties: Transparent to translucent. Color: Purple, violet, pink, peach-blossom- red, carmine, greenish white; may be nearly colorless. Streak: White. Luster: Vitreous. Optical Class: Biaxial (+). Orientation: X = a; Y = c; Z = b. Dispersion: r< v,strong. α = 1.697–1.708 β = 1.708–1.719 γ = 1.741–1.745 2V(meas.) = Moderate to small. Cell Data: Space Group: P cab. a = 10.122(1) b = 9.886(1) c = 8.7233(7) Z = 8 X-ray Powder Pattern: The Kreuzberg, Germany. (ICDD 33–667). 3.114 (100), 4.383 (85), 5.509 (60), 2.546 (50), 3.996 (45), 3.002 (45), 2.949 (45) Chemistry: (1) (2) P2O5 38.24 37.99 Fe2O3 43.40 42.73 H2O 18.89 19.28 Total 100.53 100.00 • (1) Pleystein, Germany. (2) FePO4 2H2O. Polymorphism & Series: Dimorphous with phosphosiderite, forms a series with variscite. Mineral Group: Variscite group. Occurrence: A late secondary mineral in complex granite pegmatites; in “limonite” iron ores and gossans; with magnetite iron ores; rarely a cave mineral. Association: Beraunite, hur´eaulite,dufr´enite,bermanite, stewartite, cacoxenite, rockbridgeite, vivianite, apatite, leucophosphite, phosphosiderite.
    [Show full text]
  • Using the High-Temperature Phase Transition of Iron Sulfide Minerals As
    www.nature.com/scientificreports OPEN Using the high-temperature phase transition of iron sulfde minerals as an indicator of fault Received: 9 November 2018 Accepted: 15 May 2019 slip temperature Published: xx xx xxxx Yan-Hong Chen1, Yen-Hua Chen1, Wen-Dung Hsu2, Yin-Chia Chang2, Hwo-Shuenn Sheu3, Jey-Jau Lee3 & Shih-Kang Lin2 The transformation of pyrite into pyrrhotite above 500 °C was observed in the Chelungpu fault zone, which formed as a result of the 1999 Chi-Chi earthquake in Taiwan. Similarly, pyrite transformation to pyrrhotite at approximately 640 °C was observed during the Tohoku earthquake in Japan. In this study, we investigated the high-temperature phase-transition of iron sulfde minerals (greigite) under anaerobic conditions. We simulated mineral phase transformations during fault movement with the aim of determining the temperature of fault slip. The techniques used in this study included thermogravimetry and diferential thermal analysis (TG/DTA) and in situ X-ray difraction (XRD). We found diversifcation between 520 °C and 630 °C in the TG/DTA curves that signifes the transformation of pyrite into pyrrhotite. Furthermore, the in situ XRD results confrmed the sequence in which greigite underwent phase transitions to gradually transform into pyrite and pyrrhotite at approximately 320 °C. Greigite completely changed into pyrite and pyrrhotite at 450 °C. Finally, pyrite was completely transformed into pyrrhotite at 580 °C. Our results reveal the temperature and sequence in which the phase transitions of greigite occur, and indicate that this may be used to constrain the temperature of fault-slip. This conclusion is supported by feld observations made following the Tohoku and Chi-Chi earthquakes.
    [Show full text]
  • Thermomagnetic Properties of Vivianite Nodules, Lake El'gygytgyn
    Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Clim. Past Discuss., 8, 4989–5027, 2012 www.clim-past-discuss.net/8/4989/2012/ Climate doi:10.5194/cpd-8-4989-2012 of the Past © Author(s) 2012. CC Attribution 3.0 License. Discussions This discussion paper is/has been under review for the journal Climate of the Past (CP). Please refer to the corresponding final paper in CP if available. Thermomagnetic properties of vivianite nodules, Lake El’gygytgyn, Northeast Russia P. S. Minyuk1, T. V. Subbotnikova1, L. L. Brown2, and K. J. Murdock2 1North-East Interdisciplinary Scientific Research Institute of Far East Branch of Russian Academy Science, Magadan, Russia 2Department of Geosciences, University of Massachusetts, Amherst, USA Received: 7 September 2012 – Accepted: 20 September 2012 – Published: 9 October 2012 Correspondence to: P. S. Minyuk ([email protected]) Published by Copernicus Publications on behalf of the European Geosciences Union. 4989 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Abstract Vivianite, a hydrated iron phosphate, is abundant in sediments of El’gygytgyn Lake, located in the Anadyr Mountains of Central Chukotka, Northeastern Russia (67◦300 N; 172◦050 E). Magnetic measurements, including weight low-field AC magnetic suscepti- 5 bility, field dependent magnetic susceptibility, hysteresis parameters, temperature de- pendence of the saturation magnetization, as well as susceptibility in different heating media provide ample information on vivianite. Electron-microprobe analyses, electron microscopy and energy dispersive spectroscopy were used to identify diagnostic min- erals. Vivianite nodules are abundant in both sediments of cold (anoxic) and warm −6 3 −1 10 (oxic) stages. Magnetic susceptibility of the nodules varies from 0.78 × 10 m kg to 1.72×10−6 m3 kg−1 (average = 1.05×10−6 m3 kg−1) and is higher than the susceptibility of sediments from the cold intervals.
    [Show full text]