DOCSLIB.ORG

Christite, a New Thallium Mineral from the Carlin Gold Deposit, Nevada

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Christite, a New Thallium Mineral from the Carlin Gold Deposit, Nevada American Mineralogist, Volume62, pages421425, 1977 Christite,a newthallium mineral from the Carlin golddeposit, Nevada ARruuRS. Rlorxn U.S. GeologicalSuruey, Menlo Park, California 94025 FnnNr W. Dlcrsor Departmentof Geology,Stanford Uniuersity St anfo rd, Cal ift rnia 9430 5 JoHNF. Slecr U.S. GeologicalSuruey, Reston, Virginia 22092 lNn KevtNL. Bnowx ChemistryDiuision, Diuision of Scientffic and IndustrialResearch, Petone, New Zealand Abstract Christite,TlHgAsSr, occurs with realgar,orpiment, and loranditein bariteveins and with realgar,lorandite, and getchellitein mineralizedcarbonaceous silty dolomite in the Carlin gold deposit,north-central Nevada. The mineralis namedfor Dr. CharlesL. Christof the U.S. GeologicalSurvey. The color is crimsonor deep red, but variesto bright orangein thinnerplates and crystals;the streakis bright orange,and the lusteris adamantine.The mineralis monoclinic,space group P2,/n,a -- 6.113(l),b = 16.188(4),c = 6.1Il(l) A, with0 : 96.71(2)',Z = 4, and cell volume: 600.6A8. Strongest X-ray powderdiffraction lines, in A, andtheir relative intensities are2.98 (10),3.62 (8),3.49 (6),2.692(6),2.216 (5),4.03 (6), and 3.36(5). Electronmicroprobe analyses gave Tl 35.2,Hg 35.1,As 13.1,S 16.6,sum 100.0 weight percent.The mineraloccurs in smallsubhedral to anhedralgrains which usuallylack well-developedforms but may showa bladedor flattenedhabit. Synthetic crystals are tabular, show{010) and {T0l}pinacoids, and {1l0} and {01l} prisms,and haveperfect {010}, excellent {ll0} and {001},and good {T0l} cleavages.Vickers hardness varied from 28.3-34.6and averaged31.5 kg mm-' (10 determinations).Density of syntheticTlHgAsSs is 6.2(2)(meas) and6.37g cm-e (calc).In reflectedlight christiteis grayish-whitewith a faint blue tint, lacks visiblebireflectance, is anisotropic,and has a brilliant red-orangeinternal reflection. Reflec- tancesin air are: Rsco.-= 23,7-23.9;Rsrs.- : 24.9-25.2;Rsre,- = 26.5-26.9:and Ra7s.'= 29.6-30.0. Introduction mation. Theseelements occur with gold on the sur- faces of pyrite grains and form a wide variety of The Carlin gold deposit, located about 50 km sulfide and sulfosalt minerals. Christite has been northwestof the town of Elko in north-centralNe- found in specimenscontaining large amounts of arse- vada,is the largestof the disseminatedreplacement- nic-richminerals. type gold depositsin North America.Large amounts Christiteis namedfor Dr. CharlesL. Christ of the of mercury, arsenic,antimony, and thallium are U.S. GeologicalSurvey in recognitionof his out- closelyassociated with gold in mineralizedsilty argil- standing contributions in the fields of crystallog- laceousdolomite beds in the Robert MountainsFor- raphy, mineralogy, and geochemistry.Christite is 421 422 RADTKE ET AL: CHRISTITE pronouncedkrist'-ite (as in crystal).The namehas Physicaland opticalproperties beenapproved by the Commissionof New Minerals Christite in barite veinletsoccurs in subhedral and Mineral Names of the InternationalMiner- grainsvarying from about0.5 mm to I mm in length. alogicalAssociation. The crystalsare usually bounded by grainsofrealgar The type materialis depositedin the Smithsonian andlorandite and also occur surrounded by or locked Institution,Washington, D. C., and in theCollection within orpimentcrystals. Two grainsof christitesep- of EpithermalOres and Minerals,Department of aratedfrom bariteare shown in Figurel. In theother Geology,Stanford University, Stanford, California. occurrencesmall anhedral christite grains up to 0.25 Occurrence mm in diameteroccur intergrown with lorandite,get- chellite,and realgar. Christitehas been found in two areasin the Carlin The mineral usuallylacks well-developedforms, deposit,with somewhatdifferent mineral associations althoughthe habit of somegrains is somewhatbladed and host materials.Small isolated euhedral to sub- or flattened.Synthetic crystals are tabular parallelto hedralcrystals of christiteoccur intergrown with lo- {010}and areslightly elongated parallel to the c axis. randite,realgar, and orpiment platycrystals between Dominant forms are the {010}and iTOl} pinacoids of baritein smallcavities and openspaces along the andthe {ll0i and {011}prisms. Synthetic TlHgAsS' marginsof bariteveinlets. This areais nearthe bot- hasperfect {010} cleavage, excellent {110} and {001} tom of the oxidizedsection in the East ore zone cleavage,and good {T0li cleavage.Fragments tend betweenthe 6400and 6420benches near mine coordi- to be dominatedby the micaceous{010} cleavage, but (Radtke, nates22,800 N, 19,750E 1973).Christite closely-spacedslippage along other cleavagescauses alsooccurs with abundantrealgar and small amounts fragmentsto deform ductily to smooth curved sur- oflorandite,getchellite, and an undescribednew thal- faces. lium-arsenic-sulfidemineral, in smallveinlets filling The hardnessof christiteas determinedwith a microfracturesand in smallseams and patchesalong Leitzhardness indentor with a l0 g loadranged from bedding planesin mineralizedsilty carbonaceous28.3to 34.6and averaged 31.5 kg mm-'z(10determi- dolomitebeds of the RobertsMountains Formation nations).Values for syntheticTlHgAsS, ranged from in the Eastore zone. Samples which contained christ- 27.1to33.0 and averaged 29.8 kg mm-'z(8determina- ite in this latter occurrencewere found on the 6340 tions). Theseaverage hardnesses correspond to a and 6360benches between mine coordinates23,100 valuebetween I to 2 on the Mohs scale.The density N, 20,300E and23,500 N, 20,700 E(Radtke, 1973). of the mineralcould not be determinedbecause it Christiteis onemember of a groupof primaryTl- could not be separatedcleanly from otherminerals. bearingminerals of hydrothermalorigin found at the The densityof syntheticchristite, measured using a Carlin deposit.These include Tl-bearing orpiment (Radtkeet al., 1974),lorandite, TlAsSz (Radtke el al., 1973a),carlinite, TLS (Radtke and Dickson, 1975),weissbergite, TlSbS, (Dickson and Radtke, unpublishedmanuscript), and a yetundescribed min- eral of compositionTlrAsSr. In oxidizedzones the secondarymineral avicennite, Tl2Os, has been found (Radtke, Dickson and Slack, unpublishedmanu- script);it is probablethat otherdecomposition prod- ucts of primary Tl-bearingminerals also occur at Carlin. During the main periodof hydrothermalactivity, arsenic,antimony, and thallium were depositedon surfacesof pyritegrains; gold and mercurywere also depositedon pyriteand combined with carbonaceous materialsto form variousgold and gold-mercury organiccompounds. The occurrencesof antimony- arsenic-mercury-thalliumsulfide and sulfosaltmin- Fig. l. Scanning electron microscope photograph of christite grains taken from a matrix. Fragment left is probably eralsin veinletsthat cut zonesof gold mineralization barite on lying on most prominent {010} cleavage. Fragment on right is suggestthat the veinletsformed during late-stagehy- broken across most prominent cleavage and shows characteristi- drotliermalactivity (Radtke and Dickson,1974). cally developed intersecting cleavages. RADTKE ET AL, CHRISTITE Bermanbalance, is 6.2(2)g cm-'and the calculated Table l. Reflectivitiesof christiteand syntheticTlHgAsS, densityis 6.37g cm-3. lJavelength (m) Christiteis deepred or crimsonin color and is darker than realgar.Thin platesand smallcrystals 470 546 589 are red-orangeto bright orangein color, and the Christite 29.6-30.0 26.5-26.9 24.9-25.2 23.7-23.9 streakis brightorange. The lusteris adamantine.The Synthetic 29.4-29.7 26.4-26.8 24.8-25.O 23.8-24.L color in transmittedlight rangesfrom deepred to TIHgASS3 orangein thick grainsto deeporange, yellow-orange, and yellow in successivelythinner plates.In reflected light in air the mineralis grayish-whitewith a faint for the syntheticmaterial are due in part to preferred blue tint, lacksbireflectance, and is anisotropic.The orientationsinduced by the cleavages. very strong brilliant red-orangeinternal reflection precludesdetermination of the degreeof aniso- Chemicalcomposition tropism.Optical propertiesfor syntheticTlHgAsS, Resultsof chemicalanalyses of christitedone with and christiteare similar. Data on the reflectivitiesof theelectron microprobe and the analytical conditions christiteand synthetic TlHgAsS, are given in Tablel. used are given in Table 3. The compositionis TlHgAsSr and no other elementswere presentat Crystallography levelsdetectable by microprobeanalysis. Emission Christiteis monoclinic,space group P2r/n,withZ spectrographicanalysis done on a compositesample : 4[TlHgAsSa].Unit-cell constants determined for a containingseveral hand-picked grains confirmed the syntheticcrystal are a :6.1 l3(1),b : 16.188(4),c = low levelof other elements.Other elementsdetected 6.111(l)A, with P :96.71(2)oand V : 600.6Az (weightpercent) include Sb : 0.005;Cu : 0.002;Fe (Brownand Dickson,1977). Synthetic euhedral crys- : 0.001;Pb : 0.001;Mn : 0.001;Ag : 0.0005. talsof christitedisplay typical monoclinic 2/m forms. The crystalstructure (Brown and Dickson,1977) Synthesis canbe describedas consisting of trigonalpyramids of Christite can be synthesizedby reacting fine- AsS,joined togetherby HgSatetrahedra to form a grainedmixtures of TlAsS,and HgS in stoichiomet- polymerictwo-dimensional sheet structure parallel to ric proportionsin evacuatedsealed glass tubes at {010}.Thallium atoms are situated between the sheets 290"C and below.This processproduces a powder and are weakly bondedto them. The structureof with d spacingsthat correspondvery closelywith christiteplaces it as a memberof the IIa (d : 3) thoseof the mineral(Table 2). Heatingabove 300oC group of sulfosaltsin
Load more

Recommended publications
  • The Crystal Structure of Gillulyite, TI2(As,Sb)Ssm from the Mercur Gold Deposit, Tooele County, Utah, U.S.A
    American Mineralogist, Volume 80, pages 394-399, 1995 The crystal structure of gillulyite, TI2(As,Sb)sSm from the Mercur gold deposit, Tooele County, Utah, U.S.A. FRANKLIN F. FOIT, JR. Department of Geology, Washington State University, Pullman, Washington 99164, U.S.A. PAUL D. ROBINSON Department of Geology, Southern Illinois University, Carbondale, Illinois 62901, U.S.A. JAMES R. WILSON Department of Geology, Weber State University, Ogden, Utah 84408-2507, U.S.A. ABSTRACT Gillulyite, TI2(AsH ,SbH )8S13,is monoclinic with space group P2/n and a = 9.584(3), b = 5.679(2), c = 21.501(6) A, ~ = 100.07(2)°, V = 1152.2(7) A3, and Z = 2, The average structure was determined using direct methods and refined to a final residual of 0.046 using 930 reflections. The structure consists of TI-As-S- and As-S-bearing sheets, each present statistically 50% of the time. Four sheets, linked together by Tl-S, As-S, and S-S bonds, are stacked parallel to (00 I), yielding the 21-A c-axis repeat of the average unit cell. The Tll atom within the TI-As-S sheet is coordinated by six S nearest neighbors, which form a distorted trigonal prism. The partially occupied Tl2 position between the sheets is split symmetrically about the twofold axis with a separation of 1.28 A and equal but partial occupancies of25%. The disordering of the Tl2 position and extreme distortion of its coordination polyhedron is probably the result of the Tl+ 6s2lone pair effect. The mean bond distances for the AsS3pyramids range from 2.263 to 2.319 A.
    [Show full text]
  • Theoretical Studies on As and Sb Sulfide Molecules
    Mineral Spectroscopy: A Tribute to Roger G. Bums © The Geochemical Society, Special Publication No.5, 1996 Editors: M. D. Dyar, C. McCammon and M. W. Schaefer Theoretical studies on As and Sb sulfide molecules J. A. TOSSELL Department of Chemistry and Biochemistry University of Maryland, College Park, MD 20742, U.S.A. Abstract-Dimorphite (As4S3) and realgar and pararealgar (As4S4) occur as crystalline solids con- taining As4S3 and As4S4 molecules, respectively. Crystalline As2S3 (orpiment) has a layered structure composed of rings of AsS3 triangles, rather than one composed of discrete As4S6 molecules. When orpiment dissolves in concentrated sulfidic solutions the species produced, as characterized by IR and EXAFS, are mononuclear, e.g. ASS3H21, but solubility studies suggest trimeric species in some concentration regimes. Of the antimony sulfides only Sb2S3 (stibnite) has been characterized and its crystal structure does not contain Sb4S6 molecular units. We have used molecular quantum mechanical techniques to calculate the structures, stabilities, vibrational spectra and other properties of As S , 4 3 As4S4, As4S6, As4SIO, Sb4S3, Sb4S4, Sb4S6 and Sb4SlO (as well as S8 and P4S3, for comparison with previous calculations). The calculated structures and vibrational spectra are in good agreement with experiment (after scaling the vibrational frequencies by the standard correction factor of 0.893 for polarized split valence Hartree-Fock self-consistent-field calculations). The calculated geometry of the As4S. isomer recently characterized in pararealgar crystals also agrees well with experiment and is calculated to be about 2.9 kcal/mole less stable than the As4S4 isomer found in realgar. The calculated heats of formation of the arsenic sulfide gas-phase molecules, compared to the elemental cluster molecules As., Sb, and S8, are smaller than the experimental heats of formation for the solid arsenic sulfides, but shown the same trend with oxidation state.
    [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]
  • Using 2D Gis to Assist 3D Modelling of the Zarshuran Gold Deposit, Iran
    Asadi, Hooshang USING 2D GIS TO ASSIST 3D MODELLING OF THE ZARSHURAN GOLD DEPOSIT, IRAN * Hooshang ASADI HARONI, Edmund SIDES, Kiiza NGONZI International Institute for Aerospace Survey and Earth Sciences (ITC), The Netherlands * Ministry of Higher Education, Tehran, Iran harouni @itc.nl [email protected] Technical Commission Session Themes TC VII-8 KEY WORDS: Spatial data, Integration, Geology, Geophysics, GIS, Data mining, Information extraction ABSTRACT The Zarshuran gold deposit in NW Iran is an area of historic mining for gold and arsenic with considerable potential for discovery of economic gold mineralisation. Geological, geochemical and geophysical data, collected by the Ministry of Mines and Metals were compiled and analysed in a 2-dimensional (2D) GIS. This resulted in the definition of major structural features, and lithological units, that control the gold mineralisation. Spatial modelling and interpretation of the geochemical and geophysical data showed that the mineralization is mainly controlled by chemically-reactive Precambrian carbonates and black shales, extending in a NW-SE direction, and also by NE-SW high angle faults and their intersections with NW-SE structures. The results obtained, from the 2D GIS analysis, were used in the initial phase of the construction and validation of the 3-dimensional (3D) models used for resource estimation. Comparison of the statistical analyses of geochemical data in soils and in drillcore indicated enhanced concentrations of gold in soils at surface, due to residual enrichment. An enrichment relationship was established based on interpretation of the cumulative frequency plots for gold in soil and drillcore samples. Based on this relationship the gold anomalies interpreted from the soil geochemical data were used to infer a resource potential, to a depth of 200m below surface, of 10Mt at an average grade of 0.2 g/t gold.
    [Show full text]
  • Environmental Exposure of Thallium and Potential Health Risk in an Area of High Natural Concentrations of Thallium: Southwest Guizhou, China
    Environmental Exposure and Health 367 Environmental exposure of thallium and potential health risk in an area of high natural concentrations of thallium: southwest Guizhou, China T. Xiao1, L. He1,3, J. Guha2, J. Lin1 & J. Chen1 1State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, People’s Republic of China 2Sciences de la Terre, Université du Québec à Chicoutimi, Canada 3Graduate School of Chinese Academy of Sciences, Beijing, People’s Republic of China Abstract Little is known in the literature about thallium (Tl) exposure from naturally occurring Tl contamination. This paper draws attention to the potential health risk posed by high concentrations of naturally occurring Tl in the environment. The inhabitants of a rural area of southwest Guizhou Province, China, reside within a natural Tl accumulated environment resulting from the Tl-rich sulfide mineralization, and they face a severe Tl exposure in their daily lives. The daily intake 1.9 mg Tl from the consumed food crops was estimated for a local adult inhabitant of Lanmuchang. High Tl concentrations were detected in urines of the local residents. Measured urinary Tl levels are as high as 2.51-2,668 µg/L, surpassing the accepted world urine Tl level <1 mg/L for “non-exposed” humans. However, there is a positive relationship between the extent of Tl exposure from Tl in soil and crops in the immediate environment and the levels of Tl detected in urine. This study has been able to identify that the elevated urinary Tl levels are mainly attributable to Tl accumulation in locally grown vegetables acquiring Tl from natural sources in the local soils.
    [Show full text]
  • The Importance of Minerals in Coal As the Hosts of Chemical Elements: a Review
    The importance of minerals in coal as the hosts of chemical elements: A review Robert B. Finkelmana,b, Shifeng Daia,c,*, David Frenchd a State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, China b University of Texas at Dallas, Richardson, TX 75080, USA c College of Geoscience and Survey Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China d PANGEA Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia *, Corresponding author: [email protected]; [email protected] Abstract Coal is a complex geologic material composed mainly of organic matter and mineral matter, the latter including minerals, poorly crystalline mineraloids, and elements associated with non- mineral inorganics. Among mineral matter, minerals play the most significant role in affecting the utilization of coal, although, in low rank coals, the non-mineral elements may also be significant. Minerals in coal are often regarded as a nuisance being responsible for most of the problems arising during coal utilization, but the minerals are also seen as a potentially valuable source of critical metals and may also, in some cases, have a beneficial effect in coal gasification and liquefaction. With a few exceptions, minerals are the major hosts of the vast majority of elements present in coal. In this review paper, we list more than 200 minerals that have been identified in coal and its low temperature ash, although the validity of some of these minerals has not been confirmed. Base on chemical compositions, minerals found in coal can be classified into silicate, sulfide and selenide, phosphate, carbonate, sulfate, oxide and hydroxide, and others.
    [Show full text]
  • ~Ui&£R5itt! of J\Rij!Oua
    Minerals and metals of increasing interest, rare and radioactive minerals Authors Moore, R.T. Rights Arizona Geological Survey. All rights reserved. Download date 06/10/2021 17:57:35 Link to Item http://hdl.handle.net/10150/629904 Vol. XXIV, No.4 October, 1953 ~ui&£r5itt! of J\rij!oua ~ul1etiu ARIZONA BUREAU OF MINES MINERALS AND METALS OF INCREASING INTEREST RARE AND RADIOACTIVE MINERALS By RICHARD T. MOORE ARIZONA BUREAU OF MINES MINERAL TECHNOLOGY SERIES No. 47 BULLETIN No. 163 THIRTY CENTS (Free to Residents of Arizona) PUBLISHED BY ~tti£ll~r5itt! of ~rh!Omt TUCSON, ARIZONA TABLE OF CONTENTS INTRODUCTION 5 Acknowledgments 5 General Features 5 BERYLLIUM 7 General Features 7 Beryllium Minerals 7 Beryl 7 Phenacite 8 Gadolinite 8 Helvite 8 Occurrence 8 Prices and Possible Buyers ,........................................ 8 LITHIUM 9 General Features 9 Lithium Minerals 9 Amblygonite 9 Spodumene 10 Lepidolite 10 Triphylite 10 Zinnwaldite 10 Occurrence 10 Prices and Possible Buyers 10 CESIUM AND RUBIDIUM 11 General Features 11 Cesium and Rubidium Minerals 11 Pollucite ..................•.........................................................................., 11 Occurrence 12 Prices and Producers 12 TITANIUM 12 General Features 12 Titanium Minerals 13 Rutile 13 Ilmenite 13 Sphene 13 Occurrence 13 Prices and Buyers 14 GALLIUM, GERMANIUM, INDIUM, AND THALLIUM 14 General Features 14 Gallium, Germanium, Indium and Thallium Minerals 15 Germanite 15 Lorandite 15 Hutchinsonite : 15 Vrbaite 15 Occurrence 15 Prices and Producers ~ 16 RHENIUM 16
    [Show full text]
  • Orpiment As2s3 C 2001-2005 Mineral Data Publishing, Version 1
    Orpiment As2S3 c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Monoclinic. Point Group: 2/m. Commonly in foliated columnar or fibrous aggregates, with cleavages as much as 60 cm across; may be reniform or botryoidal; also granular or powdery; rarely as prismatic crystals, to 10 cm. Twinning: On {100}. Physical Properties: Cleavage: Perfect on {010}, imperfect on {100}; cleavage lamellae are flexible. Tenacity: Sectile. Hardness = 1.5–2 VHN = n.d. D(meas.) = 3.49 D(calc.) = 3.48 Optical Properties: Transparent. Color: Lemon-yellow to golden or brownish yellow. Streak: Pale lemon-yellow. Luster: Resinous, pearly on cleavage surface. Optical Class: Biaxial (–). Pleochroism: In reflected light, strong, white to pale gray with reddish tint; in transmitted light, Y = yellow, Z = greenish yellow. Orientation: X = b; Z ∧ c = 2◦. Dispersion: r> v,strong. α = 2.4 (Li). β = 2.81 (Li). γ = 3.02 (Li). 2V(meas.) = 76◦ Anisotropism: Barely observable because of strong internal reflections. R1–R2: (400) 33.0–36.5, (420) 31.0–35.2, (440) 28.9–33.9, (460) 27.4–31.5, (480) 26.0–30.3, (500) 24.9–29.3, (520) 24.0–28.4, (540) 23.3–27.8, (560) 22.8–27.3, (580) 22.3–26.9, (600) 22.0–26.5, (620) 21.7–26.3, (640) 21.5–26.0, (660) 21.2–25.7, (680) 21.0–25.5, (700) 20.8–25.3 Cell Data: Space Group: P 21/n. a = 11.475(5) b = 9.577(4) c = 4.256(2) β =90◦41(5)0 Z=4 X-ray Powder Pattern: Baia Sprie (Fels˝ob´anya), Romania.
    [Show full text]
  • 10700 Orpiment, King's Yellow PY 39
    10700 Orpiment, King's Yellow PY 39 Chemical composition: yellow sulphide of arsenic As2S3 The origin of the modern name is derived from the Latin term auripigmentum or auripigmento, literally meaning gold paint. Orpiment was once widely used, particularly in the East, but has now fallen into disuse because of its limited supply and because of its poisonous character. The principal sources in ancient times appear to have been in Hungary, Macedonia, Asia Minor and perhaps in various parts of Central Asia. There was a large deposit near Julamerk in Kurdistan. Current deposits of orpiment are in Romania, Hungary, Germany, Greece, France, Italy, Iran, Peru, China, Japan and the western United States. Orpiment occurs as a low temperature product in hydrothermal veins, as a volcanic sublimation product, as a hot spring deposit and in fire mines. It is often associated with stibnite, pyrite, realgar, calcite and gypsum. Orpiment occurs in many places but not in large quantities. Orpiment is usually described as a lemon or canary yellow or sometimes as a golden or brownish yellow with a fair covering power. Microscopically, orpiment is crystalline and may contain orange-red particles of realgar, to which it is closely related. The larger particles glisten by reflected light and have a waxy-looking surface. The toxicity of the arsenic sulfide pigments has been known since early times. The toxic properties of orpiment have been used to advantage to repel insects. Orpiment is said to be incompatible with lead- or copper-containing pigments. Orpiment is not stable in lime and therefore can not be used for fresco, a fact noted by Cennino Cennini inn the fifteenth century.
    [Show full text]
  • Thallium Mobility in Mining Wastes at the Crven Dol Locality, Allchar Deposit, North Macedonia
    EGU2020-4959, updated on 25 Sep 2021 https://doi.org/10.5194/egusphere-egu2020-4959 EGU General Assembly 2020 © Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. Thallium mobility in mining wastes at the Crven Dol locality, Allchar deposit, North Macedonia Tamara Đorđević1, Uwe Kolitsch1,2, Petr Drahota3, Magdaléna Knappová3, Juraj Majzlan4, Stefan Kiefer4, Tomáš Mikuš5, Goran Tasev6, Todor Serafimovski6, Ivan Boev6, and Blažo Boev6 1Institut für Mineralogie und Kristallographie, Universität Wien, Althanstr. 14, A-1090 Wien, Austria 2Mineralogisch-Petrographische Abteilung, Naturhistorisches Museum, Burgring 7, A-1010 Wien, Austria 3Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University, Albertov 6, 128 43 Prague 2, Czech Republic 4Institute of Geosciences, Department of Mineralogy, Friedrich-Schiller-Universität, Carl-Zeiss-Promenade 10, 07745 Jena, Germany 5Earth Science Institute, Slovak Academy of Sciences, Geological Division, Ďumbierska 1, 974 01 Banská Bystrica, Slovakia 6Department of Mineral Deposits, Faculty of Natural Sciences, University “Goce Delčev”-Štip, Goce Delčev 89, 2000 Štip, North Macedonia In order to better understand the environmental behaviour of thallium, we have chosen the abandoned As–Sb–Tl–Au Allchar deposit (North Macedonia) with unique mineral composition and high thallium grades of the ore. We used pore water analyses, selective extractions, single-crystal and powder X-ray diffraction (PXRD), SEM-EDS, electron microprobe analysis (EMPA), and Raman spectroscopy to determine the distribution and speciation of thallium in waste dump material at the Tl-rich Crven Dol locality in the northern part of the Allchar deposit. PXRD studies showed that the various solid waste samples are comprised mostly of carbonates (dolomite and calcite), gypsum, quartz, muscovite, kaolinite-group minerals followed by orpiment, realgar, pyrite, marcasite, lorandite, and various iron and calcium arsenates and iron (hydro)oxides, both amorphous and crystalline.
    [Show full text]
  • XIII 0609.Pdf
    XIII_0609 N. Jb. Miner. Abh. Stuttgart, Oktober 1994 Possibilities of concentrating the thallium minerallorandite from the Allchar deposit, Crven Dol region By Blagoja Petrov, Donka Andonova, Trajce Stafilov and Tome Novakovski, Skopje With 3 figures and 3 tables in the text PETROV, B., ANDONOVA, D. STAHLOV, T. & NOVAKOVSKJ, T.: Possibilities of concentrating the thallium mineral from the Allchar deposit , Crven Dol region . ­ N. jb. Miner. Abh. 167: 413-420; Stuttgart 1994. Abstract: The paper presents results obta ined by laboratory testings on th e possibilities of concentrating the thallium minerallorandite from ore in the Allchar deposit, Crven Dol region. For concentrating the lorandite from ore, stand ard methods were used: gravity concentrating in heavy liquids, gravity concentrating on a concentrating table, high intensity magnetic separation by an isodynamic separator "Fr ant z" as well as their combinations. From the -preconcentrates obtained, pure grains of lorandire were sepa­ rated by picking of individual grains. Ke y w 0 r d s: Thallium minerals; lorandite minera l; concentrating lor andite; gravity concentrating; high intensity magnetic separation. Introduction Thallium belongs to the rare metals. According to Arence, the average thallium content in the Earth's crust amounts to about 0.003 %. It mostly appears in a form of solid solution in the lattices of sulfide minerals. Thal­ lium, very seldom, forms its own minerals. Most frequently, it is in para­ genesis with the sulfide minerals particularly galenite, sphalerite, mar casite and pyrite. Usually, it can be obtained as a by-product when roasting pyrite for the production of sulphuric acid and smelting of lead and zinc.
    [Show full text]
  • Intriguing Minerals: Lorandite, Tlass2, a Geochemical Detector of Solar
    ChemTexts (2019) 5:12 https://doi.org/10.1007/s40828-019-0086-3 LECTURE TEXT Intriguing minerals: lorandite, TlAsS2, a geochemical detector of solar neutrinos Gligor Jovanovski1,2 · Blažo Boev3 · Petre Makreski2 · Trajče Staflov2 · Ivan Boev3 Received: 1 April 2019 / Accepted: 15 April 2019 © Springer Nature Switzerland AG 2019 Abstract This lecture text demonstrates how the mineral lorandite is used as a detector of solar neutrinos. Because the age of the lorandite deposit in Allchar, North Macedonia, is known, this opened the possibility to determine the solar neutrino fux over the last 4.3 million years. Keywords Lorandite · Thallium · Lead · Mineral · Neutrino Lorandite darker red color, semimetallic luster and perfect cleavage along the (001), (201) and (110) planes. Some crystals are Lorandite (or lorándite), TlAsS2, is well known as the most coated with a brownish yellow crust. Lorandite crystals common thallium-containing mineral [1, 2]. It was frst of 1 cm are typical for this site, although exceptional sin- discovered in the Allchar mine, Macedonia, in 1894 [3–5], gle crystals up to 5 cm have also been found. Lorandite is and the frst chemical analysis was performed by Loczka named in honor of the Hungarian physicist Loránd Eötvös [6]. Smaller quantities were later found in other localities (1848–1919) (Fig. 1). worldwide: the Dzhizhikrut Sb–Hg mine in Tajikistan, the The Allchar locality has been known since the twelfth Beshtau uranium deposit in Russia, the Lanmuchang Hg–Tl or thirteenth century, and according to other estimations, deposit in China, the Zarshuran gold mine in Iran, the Len- even longer.
    [Show full text]