Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-26T20:57:06.011Z Has data issue: false hasContentIssue false

Klajite, MnCu4(AsO4)2(AsO3OH)2(H2O)10, from Jáchymov (Czech Republic): the second world occurrence

Published online by Cambridge University Press:  05 July 2018

J. Plášil*
Affiliation:
Institute of Physics ASCR, v.v.i., Na Slovance 2, Prague 8, 182 21, Czech Republic
A. V. Kasatkin
Affiliation:
V/O "Almazjuvelirexport", Ostozhenka str., 22, block 1, 119034 Moscow, Russia
R. Škoda
Affiliation:
Department of Geological Sciences, Masaryk University, Kotlářská 2, Brno, 611 37, Czech Republic
P. Škácha
Affiliation:
Mining Museum Příbram, Hynka Kličky Place 293, 261 01, Příbram VI – Březové Hory, Czech Republic Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University in Prague, Albertov 6, 128 43, Prague 2, Czech Republic
*

Abstract

Klajite, MnCu4(AsO4)2(AsO3OH)2(H2O)10, the Mn-Cu-bearing member of the lindackerite group, was found in Jáchymov, Czech Republic, as the second world occurrence. It is associated with ondrušite and other arsenate minerals growing on the quartz gangue with disseminated primary sulfides, namely tennantite and chalcopyrite. Electron-microprobe data showed klajite aggregates to be chemically inhomogeneous at larger scales, varying from Mn-Ca-rich to Cu-rich domains. The chemical composition of the the Mn-rich parts of aggregates can be expressed by the empirical formula (Mn0.46Ca0.22Cu0.07Mg0.02)∑0.77(Cu3.82Mg0.14Ca0.03Zn0.01)∑4.00(As1.94Si0.06)∑2.00O8[AsO2.73(OH)1.27]2(H2O)10 (mean of seven representative spots; calculated on the basis of As + Si + P = 4 a.p.f.u. (atoms per formula unit) and 10 H2O from ideal stoichiometry), showing a slight cationic deficiency at the key Me-site. According to single-crystal X-ray diffraction, klajite from Jáchymov is triclinic, P, with a = 6.4298(8), b = 7.9716(8), c = 10.707(2) Å, α = 85.737(12)°, β = 80.994(13)°, γ = 84.982(10)°, and V = 538.85(14) Å3, Z = 1. The crystal structure was refined to R1 = 0.0628 for 1034 unique observed reflections (with Iobs > 3σ(I)), confirming that klajite (Mn-Cu member) and ondrušite (Ca-Cu member) are isostructural. The current data-set allowed determination of the positions of several hydrogen atoms. Discussion on hydrogen bonding networks in the structure of klajite as well as detailed bond-valence analysis are provided.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2014

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

Brown, I.D. (1981) The bond-valence method: an empirical approach to chemical structure and bonding. Pp. 1–30 in: Structure and Bonding in Crystals II (M. O’Keeffe and A. Navrotsky, editors). Academic Press, New York.Google Scholar
Brown, I.D. (2002) The Chemical Bond in Inorganic Chemistry. The Bond Valence Model. Oxford University Press, Oxford, UK.Google Scholar
Brown, I.D. and Altermatt, D. (1985) Bond-valence parameters obtained from a systematic analysis of the inorganic crystal structure database. Acta Crystallographica, B41, 244248.CrossRefGoogle Scholar
Burke, E.A.J., Sejkora, J., Sarp, H. and Chiappero, P.-J. (2007) Revalidation of pradetite as a mineral. Archive des Sciences (Geneve), 60, 5154.Google Scholar
Clark, R.C. and Reid, J.S. (1995) The analytical calculation of absorption in multifaceted crystals. Acta Crystallographica, A51, 887897.CrossRefGoogle Scholar
Dorner, R. and Weber, K. (1976) Die Kristallstruktur von Chudobait, (Mg,Zn)5H2(AsO4)4·10H2O. Naturwissenschaften, 63, 243.CrossRefGoogle Scholar
Graeser, S., Schwander, H., Bianchi, R., Pilati, T. and Gramaccioli, C.M. (1989) Geigerite, the Mn analogue of chudobaite: its description and crystal structure. American Mineralogist, 74, 676684.Google Scholar
Hybler, J., Ondruš, P., Císařová, I., Petříček, V. and Veselovský , F. (2003) Crystal structure of lindackerite, (Cu,Co,Ni)Cu4(AsO4)2(AsO3OH)2·9H2O, from Jáchymov, Czech Republic. European Journal of Mineralogy, 15, 10351042.CrossRefGoogle Scholar
Oszlányi, G. and Sütő, A. (2004) Ab initio structure solution by charge flipping. Acta Crystallographica, A60, 134141.CrossRefGoogle Scholar
Oszlányi, G. and Sütő, A. (2008) The charge flipping algorithm. Acta Crystallographica, A64, 123134.CrossRefGoogle Scholar
Palatinus, L. (2013) The charge flipping algorithm in crystallography. Acta Crystallographica, B69, 116.CrossRefGoogle Scholar
Palatinus, L. and Chapuis, G. (2007) Superflip – a computer program for the solution of crystal structures by charge flipping in arbitrary dimensions. Journal of Applied Crystallography, 40, 451456.CrossRefGoogle Scholar
Petříček, V., Dušek, M. and Palatinus, L. (2006) JANA2006. The Crystallographic Computing System. Institute of Physics, Praha, Czech Republic. Can be downloaded from http://jana.fzu.cz.Google Scholar
Plášil, J., Škácha, P., Sejkora, J., Novák, M., Veselovský, F., Škoda, R., Čejka, J., Ondruš, P. and Kasatkin, A.V. (2013) Hloušekite, IMA 2013- 048. CNMNC Newsletter No. 17, October 2013, page 3001, Mineralogical Magazine, 77, 29973005.Google Scholar
Pouchou, J.L. and Pichoir, F. (1985) “PAP” (jrZ) procedure for improved quantitative microanalysis. Pp. 104–106 in: Microbeam Analysis (J.T. Armstrong, editor). San Francisco Press, San Francisco, California, USA.Google Scholar
Sarp, H. and Dominik, B. (1995) Redéfinition de la Lindackerite: sa formule chimique, ses données cristallographiques et optiques. Archive des Sciences (Geneve), 48, 239250.Google Scholar
Sejkora, J., Ondruš, P. and Novák, M. (2010) Veselovský ite, triclinic (Zn,Cu,Co)Cu4(AsO4)2 (AsO3OH)2·9H2O, a Zn-dominant analogue of lindackerite. Neues Jahrbuch für Mineralogie Abhandlungen, 187, 8390.CrossRefGoogle Scholar
Sejkora, J., Plášil, J., Veselovský, F., Císařová, I. and Hloušek, J. (2011) Ondrušite, CaCu4(AsO4)2 (AsO3OH)2·10H2O, a new mineral species from the Jáchymov ore district, Czech Republic: description and crystal-structure determination. The Canadian Mineralogist, 49, 885897.CrossRefGoogle Scholar
Strunz, H. (1960) Chudobait, ein neues Mineral von Tsumeb. Neues Jahrbuch für Mineralogie, Monatshefte, 1–7.Google Scholar
Szakáll, S., Fehér, B., Bigi, S. and Mádai, F. (2011) Klajite from Recsk (Hungary), the first Mn-Cu arsenate mineral. European Journal of Mineralogy, 29, 829835.CrossRefGoogle Scholar
Vogl, J.F. (1853) Lindackerit, eine neue Mineralspecies, und Lavendulan von Joachimsthal , nebst Bemerkungen über die Erzführung der Gänge. Jahrbuch der Kaiserliche-Königliche Geologisches Reichanstalts, 4, 552557.Google Scholar