Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-19T21:53:47.006Z Has data issue: false hasContentIssue false
  • English
  • Français

Iangreyite: a new secondary phosphate mineral closely related to perhamite

Published online by Cambridge University Press:  05 July 2018

S. J. Mills ,
A. R. Kampf ,
J. Sejkora ,
P. M. Adams ,
W. D. Birch  and
J. Plášil
S. J. Mills*
Affiliation:
Department of Earth and Ocean Sciences, University of British Columbia, Vancouver, BC, Canada V6T 1Z4 Mineral Sciences Department, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, California 90007, USA Geosciences, Museum Victoria, GPO Box 666, Melbourne 3001, Victoria, Australia
A. R. Kampf
Affiliation:
Mineral Sciences Department, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, California 90007, USA
J. Sejkora
Affiliation:
Department of Mineralogy and Petrology, National Museum Prague, Vaclavské nám. 68, CZ-115 79 Praha 1, Czech Republic
P. M. Adams
Affiliation:
126 South Helberta Avenue, #2, Redondo Beach, California 90277, USA
W. D. Birch
Affiliation:
Geosciences, Museum Victoria, GPO Box 666, Melbourne 3001, Victoria, Australia
J. Plášil
Affiliation:
Department of Mineralogy and Petrology, National Museum Prague, Vaclavské nám. 68, CZ-115 79 Praha 1, Czech Republic Department of Geological Sciences, Masaryk University, Kotlářská 2, Brno, 611 37, Czech Republic
*
*E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

Iangreyite, ideally Ca2Al7(PO4)2(PO3OH)2(OH,F)15·8H2O, is a new mineral (IMA2009-087) from the Silver Coin mine, Nevada, USA and the Krásno ore district, Horní Slavkov, Czech Republic. At Silver Coin, iangreyite occurs as thin, colourless to white or cream, hexagonal tablets up to 0.4 mm in diameter and 0.02 mm thick associated with meurigite-Na, plumbogummite, kidwellite, lipscombite. strengite, chalcosiderite, wardite, leucophosphite, wavellite, goethite, barite, quartz and F-rich perhamite. At Krásno, white, yellowish or light pink iangreyite coatings consist of 0.3 mm wide clusters of minute and very thin intergrown tabular crystals with a maximum diameter of 0.2 mm. Individual iangreyite crystals are transparent with a vitreous lustre, while iangreyite clusters tend to be pearly and translucent. The estimated hardness is 3 on the Mohs scale, the fracture is irregular and the mineral is non-fluorescent under SW and LW ultraviolet light. Individual crystals are somewhat flexible and there is perfect cleavage on ﹛001﹜. The density (Silver Coin), measured by the sink-float method in an aqueous solution of sodium polytungstate, is 2.46(3) g/cm3, while the calculated density is 2.451 g/cm3. Crystals from Silver Coin are uniaxial (+), with the indices of refraction: ε = 1.544(2) and s = 1.554(2), measured in white light, and are non-pleochroic. The empirical formula for iangreyite from Silver Coin (calculated on the basis of 39 anions per formula unit) is: Ca1.42K0.22Na0.09Ba0.03 Sr0.01Al6.51Mg0.09Fe0.02Cu0.01Zn0.01P3.81F5.24H30.21O33.76, while the empirical formula from Krásno is: Ca2.15K0.10Na0.01Ba0.02Sr0.12Al6.28Mg0.01Fe0.12Cu0.08Zn0.01P3.64Si0.43F4.65H29.62O34.35. Iangreyite is trigonal, space group P321 and Z = 1, with the unit-cell parameters (Silver Coin): a = 6.988(1), c = 16.707(3) Å and V= 706.5(2) Å3 and (Krasno): a = 6.989(1), c = 16.782(4) Å and V = 709.8(2) Å3. The structure of iangreyite, modelled from powder data, consists of blocks of the crandallite-type structure that are interconnected along c via corner-sharing of crandallite-block PO4 tetrahedra with A1O2(OH)3 bipyramids. This linkage generates large channels along [110] bounded by 10-member rings of octahedra, tetrahedra and trigonal biyramids, that are occupied by Ca and water molecules.

Keywords

iangreyiteperhamitecrystal structurealunite supergroupnew mineralSilver Coin mineUSAKrásno ore districtCzech Republic
Type
CNMNC Newsletter 8
Information
Mineralogical Magazine , Volume 75 , Issue 2 , April 2011 , pp. 327 - 336
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Beran, P. and Sejkora, J. (2006) The Krásno Sn-W ore district near Horní Slavkov: mining history, geological and mineralogical characteristics. Journal of the Czech Geological Society, 51, 3-42.Google Scholar
Blount, A.M. (1974) The crystal structure of crandallite. American Mineralogist, 59, 41-47.Google Scholar
Chukanov, N.V., Pekov, I.V., Möckel, S., Zadov, A.E. and Dubinchuk, V.T. (2006) Zinclipscombite ZnFe3+ 2 (PO4)2(OH)2 – anew mineral. Proceedings of the Russian Mineralogical Society, 135, 13-18.Google Scholar
Farmer, V. C. (1974) The Infrared Spectra of Minerals. Monograph 4, Mineralogical Society, London.CrossRefGoogle Scholar
Grey, I.E., Mumme, W.G., Bordet, P. and Mills, S. J. (2008) A new crystal-chemical variation of the alunite-type structure in monoclinic PbZn0.5 Fe3(AsO4)2(OH)6 . The Canadian Mineralogist, 46, 1355-1364.CrossRefGoogle Scholar
Grey, I.E., Mumme, W.G., Mills, S.J., Birch, W.D. and Wilson, N.C. (2009) The crystal chemical role of zinc in alunite-type minerals: structure refinements for pure and zincian kintoreite. American Mineralogist, 94, 676-683.CrossRefGoogle Scholar
Kampf, A.R., Adams, P.M., Kolitsch, U. and Steele, I.M. (2009) Meurigite-Na, a new species, and the relationship between phosphofibrite and meurigite. American Mineralogist, 94, 720-727.CrossRefGoogle Scholar
Libowitzky, E. (1999) Correlation of O-H stretching frequencies and O-H…O hydrogen bond lengths in minerals. Monatshefte für Chemie, 130, 1047-1059.CrossRefGoogle Scholar
Mandarino, J.A. (1981) The Gladstone-Dale relationship: Part IV. The compatibility concept and its application. The Canadian Mineralogist, 19, 441-450.Google Scholar
Mills, S., Mumme, G., Grey, I. and Bordet, P. (2006) The crystal structure of perhamite. Mineralogical Magazine, 70, 201-209.CrossRefGoogle Scholar
Mills, S.J., Grey, I.E., Mumme, W.G., Miyawaki, R., Matsubara, S., Bordet, P., Birch, W.D. and Raudsepp, M. (2008) Kolitschite, a new arsenate mineral from Broken Hill, New South Wales, Australia. Australian Journal of Mineralogy, 14, 15-19.Google Scholar
Pouchou, J.L. and Pichoir, F. (1985) “PAP” (ϕρZ) procedure for improved quantitative microanalysis. Pp. 104-106 in: Microbeam Analysis (Armstrong, J.T., editor). San Francisco Press, San Francisco, California, USA.Google Scholar
Rodriguez-Carvajal, J. (1990) FULLPROF: A Program for Rietveld Refinement and Pattern Matching Analysis. Satellite meeting on powder diffraction of the XV Congress of the IUCr, Toulouse, France, 27 pp.Google Scholar
Scarlett, N.V.Y., Grey, I. E. and Brand, H. A. (2010) Ordering of iron vacancies in monoclinic jarosites. American Mineralogist, 95, 1590-1593.CrossRefGoogle Scholar
Sejkora, J., Škoda, R. and Ondruš, P. (2006a) New naturally occurring mineral phases from the Krásno-Horní Slavkov area, western Bohemia, Czech Republic. Journal of the Czech Geological Society, 51, 159-187.Google Scholar
Sejkora, J., Škoda, R., Ondruš, P., Beran, P. and Sü sser, C. (2006b) Mineralogy of phosphate accumulations in the Huber stock, Krásno ore district, Slavkovskýles area, Czech Republic. Journal of the Czech Geological Society, 51, 103-147.Google Scholar
Thomssen, D. and Wise, W.S. (2004) Special list: Silver Coin Mine, Iron Point district, EdnaMounta ins, Humboldt Co., Nevada, USA. International Micromounter's Journal, 13, 7-8.Google Scholar
Vanderburg, W.O. (1988) Mines of Humboldt and Pershing Counties. Nevada Publications, Las Vegas (reissue of U.S. Bureau of Mines Information Circular 6995, Reconnaissance of mining districts in Humboldt County, Nevada, 1938). 336Google Scholar