Skip to main content Accessibility help
×
Home

Juansilvaite, Na5Al3[AsO3(OH)]4[AsO2(OH)2]2(SO4)2·4H2O, a new arsenate-sulfate from the Torrecillas mine, Iquique Province, Chile

Published online by Cambridge University Press:  02 January 2018

Anthony R. Kampf
Affiliation:
Mineral Sciences Department, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA
Barbara P. Nash
Affiliation:
Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah 84112, USA
Maurizio Dini
Affiliation:
Pasaje San Agustin 4045, La Serena, Chile
Arturo A. Molina Donoso
Affiliation:
Los Algarrobos 2986, Iquique, Chile
Corresponding
E-mail address:

Abstract

The new mineral juansilvaite (IMA2015-080), Na5Al3[AsO3(OH)]4[AsO2(OH)2]2(SO4)2·4H2O, was foOptically, juansilvaiteund at the Torrecillas mine, Iquique Province, Chile, where it occurs as asecondary alteration phase in association with anhydrite, canutite, halite, sulfur and a mahnertite-like phase. Juansilvaite occurs as bright pink blades up to ∼0.5 mm long grouped in tightly intergrown radial aggregates and also as opaque dull pale pink rounded aggregates. Blades areflattened on {001}, elongated on [100] and exhibit the forms {001}, {111} and {201}. Crystals are transparent, with vitreous lustre and white streak. The Mohs hardness is ∼2½, tenacity is brittle and fracture is irregular. Cleavage is very good on {001}. The measured density is3.01(2) g cm–3 and the calculated density is 3.005 g cm–3. Optically, juansilvaite is biaxial (+) with α= 1.575(1), β = 1.597(1), γ= 1.623(1) and 2V = 86(1)° (measured in white light). Dispersion is r < v, slight, andthe orientation is X = b; Z ^ c = 27° in the obtuse angle β. The pleochroism is X > YZ in shades of pale pink. The mineral is slowly soluble in dilute HCl at room temperature. The empirical formula, determined from electron-microprobeanalyses, is Na4.95Al2.28Fe0.50 3+Mn0.21 3+Cu0.04As5.92S1.83O36H17.37. Juansilvaite is monoclinic, C2/c, a = 18.1775(13), b = 8.6285(5), c= 18.5138(13) Å, β = 90.389(6)°, V = 2903.7(3) Å3 and Z = 4. The eight strongest powder X-ray diffraction lines are [d obs Å(I)(hkl)]: 9.25(100)(002), 7.20(34)(111), 4.545(34)(400), 3.988(39)(114), 3.363(42)(314), 3.145(66)(512,420), 2.960(68)(422,422) and 2,804(33)(131,423). The structure of juansilvaite (R 1 = 3.82% for 2040 F o > 4σF reflections) contains layers made up of alternating corner-linked Al–O octahedra and acid-arsenate tetrahedra. Sodium cations occur both peripheral to the layers and within cavities in the layers. An SO4 tetrahedron and an H2O group also are in the interlayer region.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2017

Access options

Get access to the full version of this content by using one of the access options below.

References

Boudjada, A. and Guitel, J.C. (1981) Structure cristalline d'un orthoarsénate acide de fer(III) pentahydraté: Fe(H2AsO4)3-5H2O. Acta Crystallographica, B37, 14021405.CrossRefGoogle Scholar
Brown, I.D. and Altermatt, D. (1985) Bond-valence parameters from a systematic analysis of the inorganic crystal structure database. Acta Crystallographica, B41, 244247.CrossRefGoogle Scholar
Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G.L., Giacovazzo, C., Mallamo, M., Mazzone, A., Polidori, G. and Spagna, R. (2012) SIR2011: a new package for crystal structure determination and refinement. Journal of Applied Crystallography, 45, 357361.CrossRefGoogle Scholar
Cameron, E.M., Leybourne, M.I. and Palacios, C. (2007) Atacamite in the oxide zone of copper deposits in northern Chile: involvement of deep formation waters. Mineralium Deposita, 42, 205218.CrossRefGoogle Scholar
Demartin, F., Castellano, C., Gramaccioli, C.M. and Campostrini, I. (2010) Aluminum-for-iron substitution, hydrogen bonding and a novel structure type in coquimbite-like minerals. The Canadian Mineralogist, 48, 323333.CrossRefGoogle Scholar
Dick, S., Goßner, U., Weiß, A., Robl, C., Großmann, G., Ohms, G. and Zeiske, T. (1998) Taranakite-the mineral with the longest crystallographic axis. lnorganica Chimica Acta, 269, 4757.CrossRefGoogle Scholar
Gutiérrez, H. (1975) Informe sobre una rápida visita a la mina de arsénico nativo, Torrecillas. Instituto de Investigaciones Geológicas, Iquique, Chile.Google Scholar
Higashi, T. (2001) ABSCOR. Rigaku Corporation, Tokyo.Google Scholar
Kampf, A.R., Sciberras, M.J., Williams, P.A., Dini, M. and Molina Donoso, A.A. (2013a) Leverettite from the Torrecillas mine, Iquique Provence, Chile: the Co-analogue of herbertsmithite. Mineralogical Magazine, 77, 30473054.CrossRefGoogle Scholar
Kampf, A.R., Nash, B.P., Dini, M. and Molina Donoso, A. A. (2013b) Magnesiokoritnigite, Mg(AsO3OH)-H2O, from the Torrecillas mine, Iquique Province, Chile: the Mg-analogue of koritnigite. Mineralogical Magazine, 77, 30813092.CrossRefGoogle Scholar
Kampf, A.R., Mills, S.J., Nash, B.P., Housley, R.M., Rossman, G.R. and Dini, M. (2013c) Camaronesite, [Fe3+(H2O)2(PO3OH)]2(SO4)-1-2H2O, a new phosphate-sulfate from the Camarones Valley, Chile, structurally related to taranakite. Mineralogical Magazine, 77, 453465.CrossRefGoogle Scholar
Kampf, A.R., Nash, B.P., Dini, M. and Molina Donoso, A. A. (2014a) Torrecillasite, NaAs,Sb)3+4O6Cl, a new mineral from the Torrecillas mine, Iquique Province, Chile: description and crystal structure. Mineralogical Magazine, 78, 747755.CrossRefGoogle Scholar
Kampf, A.R., Mills, S.J., Hatert, F., Nash, B.P., Dini, M. and Molina Donoso, A.A. (2014b) Canutite, NaMn3 [AsO4]2[AsO2(OH)2], a new protonated alluaudite-group mineral from the Torrecillas mine, Iquique Province, Chile. Mineralogical Magazine, 78, 787795.CrossRefGoogle Scholar
Kampf, A.R., Nash, B., Dini, M. and Molina Donoso, A. A. (2015) Juansilvaite, IMA 2015-080. CNMNC Newsletter No. 28, December 2015, page 1863. Mineralogical Magazine, 79, 18591864.Google Scholar
Kampf, A.R., Nash, B.P., Dini, M. and Molina Donoso, A.A. (2016a) Chongite, Ca3Mg2(AsO4)2(AsO3OH)2-4H2O, a new arsenate member of the hureaulite group from the Torrecillas mine, Iquique Province, Chile. Mineralogical Magazine, 80, 12551263.CrossRefGoogle Scholar
Kampf, A.R., Nash, B.P., Dini, M. and Molina Donoso, A.A. (2016b) Gajardoite, KCa,,5As4+O6Cl2-5H2O, a new mineral related to lucabindiite and torrecillasite from the Torrecillas mine, Iquique Province, Chile. Mineralogical Magazine, 80, 12651272.CrossRefGoogle Scholar
Mandarino, J.A. (2007) The Gladstone-Dale compatibility of minerals and its use in selecting mineral species for further study. The Canadian Mineralogist, 45, 13071324.CrossRefGoogle Scholar
Majzlan, J., Ðorđevic, T., Kolitsch, U. and Schefer, J. (2010) Hydrogen bonding in coquimbite, nominally Fe2(SO4)3-9H2O, and the relationship between coquimbite and paracoquimbite. Mineralogy and Petrology, 100, 241248.CrossRefGoogle Scholar
Pouchou, J.-L. and Pichoir, F. (1991) Quantitative analysis of homogeneous or stratified microvo-lumes applying the model “PAP.” Pp. 3l-75 in: Electron Probe Quantitation (K.F.J. Heinrich and D.E. Newbury, editors). Plenum Press, New York.Google Scholar
Sheldrick, G.M. (2008) A short history of SHELX. Acta Crystallographica, A64, 112122.CrossRefGoogle Scholar
Wood, R.M. and Palenik, G.J. (1999) Bond valence sums in coordination chemistry. Sodium-oxygen complexes. Inorganic Chemistry, 38, 39263930.CrossRefGoogle Scholar

Full text views

Full text views reflects PDF downloads, PDFs sent to Google Drive, Dropbox and Kindle and HTML full text views.

Total number of HTML views: 0
Total number of PDF views: 20 *
View data table for this chart

* Views captured on Cambridge Core between 02nd January 2018 - 17th January 2021. This data will be updated every 24 hours.

Hostname: page-component-77fc7d77f9-kstv4 Total loading time: 0.567 Render date: 2021-01-17T13:52:50.364Z Query parameters: { "hasAccess": "0", "openAccess": "0", "isLogged": "0", "lang": "en" } Feature Flags last update: Sun Jan 17 2021 13:03:32 GMT+0000 (Coordinated Universal Time) Feature Flags: { "metrics": true, "metricsAbstractViews": false, "peerReview": true, "crossMark": true, "comments": true, "relatedCommentaries": true, "subject": true, "clr": true, "languageSwitch": true, "figures": false, "newCiteModal": false, "shouldUseShareProductTool": true, "shouldUseHypothesis": true, "isUnsiloEnabled": true }

Send article to Kindle

To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Juansilvaite, Na5Al3[AsO3(OH)]4[AsO2(OH)2]2(SO4)2·4H2O, a new arsenate-sulfate from the Torrecillas mine, Iquique Province, Chile
Available formats
×

Send article to Dropbox

To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

Juansilvaite, Na5Al3[AsO3(OH)]4[AsO2(OH)2]2(SO4)2·4H2O, a new arsenate-sulfate from the Torrecillas mine, Iquique Province, Chile
Available formats
×

Send article to Google Drive

To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

Juansilvaite, Na5Al3[AsO3(OH)]4[AsO2(OH)2]2(SO4)2·4H2O, a new arsenate-sulfate from the Torrecillas mine, Iquique Province, Chile
Available formats
×
×

Reply to: Submit a response


Your details


Conflicting interests

Do you have any conflicting interests? *