Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-15T05:22:12.921Z Has data issue: false hasContentIssue false

Kapellasite, Cu3Zn(OH)6CI2, a new mineral from Lavrion, Greece, and its crystal structure

Published online by Cambridge University Press:  05 July 2018

W. Krause*
Affiliation:
Henriette-Lott-Weg 8, D-50354 Hürth, Germany
H.-J. Bernhardt
Affiliation:
Institut für Mineralogie, Ruhr-Universität Bochum, Universitätsstraβe 150, D-44780 Bochum, Germany
R.S.W. Braithwaite
Affiliation:
School of Chemistry, Faraday Building, University of Manchester, Manchester M60 1QD, UK
U. Kolitsch
Affiliation:
Institut für Mineralogie und Kristallographie, Universität Wien, Geozentrum, Althanstraβe 14, A-1090 Wien, Austria
R. Pritchard
Affiliation:
School of Chemistry, Faraday Building, University of Manchester, Manchester M60 1QD, UK
*

Abstract

Kapellasite, Cu3Zn(OH)6Cl2, is a new secondary mineral from the Sounion No. 19 mine, Kamariza, Lavrion, Greece. It is a polymorph of herbertsmithite. Kapellasite forms crusts and small aggregates up to 0.5 mm, composed of bladed or needle-like indistinct crystals up to 0.2 mm long. The colour is green-blue, the streak is light green-blue. There is a good cleavage parallel to ﹛0001﹜. Kapellasite is uniaxial negative, ω = 1.80(1), ε = 1.76(1); pleochroism is distinct, with E = pale green, O = green-blue. Dmeas = 3.55(10) g/cm3; Dcalc. = 3.62 g/cm3. Electron microprobe analyses of the type material gave CuO 58.86, ZnO 13.92, NiO 0.03, CoO 0.03, Fe2O3 0.04, Cl 16.70, H2O (calc.) 12.22, total 101.80, less O = Cl 3.77, total 98.03 wt.%. The empirical formula is (Cu3.24Zn0.75)Σ3.99(OH)5.94Cl2.06, based on 8 anions. The five strongest XRD lines are [d in Å (I/I0, hkl)] 5.730 (100, 001), 2.865 (11, 002), 2.730 (4, 200), 2.464 (9, 021/201), 1.976 (5, 022/202). Kapellasite is trigonal, space group Pml, unit-cell parameters (from single-crystal data) a = 6.300(1), c = 5.733(1) Å, V= 197.06(6) Å3, Z = 1. The crystal structure of kapellasite is based on brucite-like sheets parallel to (0001), built from edge-sharing distorted M(OH,Cl)6 (M = Cu, Zn) octahedra. The sheets stack directly on each other (…AAA… stacking). Bonding between adjacent sheets is only due to weak hydrogen and O…C1 bonds. The name is in honour of Christo Kapellas (1938–2004), collector and mineral dealer from Kamariza, Lavrion, Greece.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2006

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

Braithwaite, R.S.W., Mereiter, K., Paar, W.H. and Clark, A.M. (2004) Herbertsmithite, Cu3Zn(OH)6Cl2, a new species, and the definition of paratacamite. Mineralogical Magazine, 68, 527539.CrossRefGoogle Scholar
Brese, N.E. and O'Keeffe, M. (1991) Bond-valence parameters for solids. Ada Crystallographica, B47, 192197.Google Scholar
Brown, I.D. (1996) VALENCE: a program for calculating bond valences. Journal of Applied Crystallography, 29, 479480.CrossRefGoogle Scholar
Deyu, L., O'Connor, B.H., Roach, G.I.D. and Cornell, J.B. (1990) Use of X-ray powder diffraction Rietveld pattern-fitting for characterising preferred orientation in gibbsite. Powder Diffraction, 5, 7985.CrossRefGoogle Scholar
Feitknecht, W. and Maget, K. (1949a) Zur Chemie und Morphologie der basischen Salze zweiwertiger Metalle, XIV. Die Hydroxychloride des Kupfers. Helvetica Chimica Acta, 32, 16391653 (in German).CrossRefGoogle Scholar
Feitknecht, W. and Maget, K. (19496) Uber Doppelhydroxyde und basische Doppelsalze. Uber basische Doppelchloride des Kupfers. Helvetica Chimica Acta, 32, 16531667.(in German).CrossRefGoogle Scholar
Fleet, M.E. (1975) The crystal structure of paratacamite, Cu2(OH)3Cl. Acta Crystallographica, B31, 183187.CrossRefGoogle Scholar
Grice, J.D., Szymanski, J.T. and Jambor, J.L. (1996) The crystal structure of clinoatacamite. The Canadian Mineralogist, 34, 7378.Google Scholar
Hawthorne, F.C. (1985) Refinement of the crystal structure of botallackite. Mineralogical Magazine, 49, 8789.CrossRefGoogle Scholar
Jambor, J.L., Dutrizac, J.E., Roberts, A.C., Grice, J.D. and Szymanski, J.T. (1996) Clinoatacamite, a new polymorph of Cu2(OH)3Cl, and its relationship to paratacamite and “anarakite”. The Canadian Mineralogist, 34, 6172.Google Scholar
Mandarino, J.A. (1981) The Gladstone-Dale relationship: part IV. The compatibility concept and its application. The Canadian Mineralogist, 19, 441450.Google Scholar
Nickel, E.H. (1995) Definition of a mineral. European Journal of Mineralogy, 7, 12131215.CrossRefGoogle Scholar
Oswald, H.R. and Feitknecht, W. (1964) Uber Hydroxidhalogenide Me2(OH)3Cl, -Br, -J zweiwertiger Metalle (Me = Mg, Ni, Co, Cu, Fe, Mn). Helvetica Chimica Acta, 47, 272289 (in German).CrossRefGoogle Scholar
Otwinowski, Z., Borek, D., Majewski, W. and Minor, W. (2003) Multiparametric scaling of diffraction intensities. Acta Crystallographica, A59, 228234.CrossRefGoogle Scholar
Parise, J.B. and Hyde, B.G. (1986) The structure of atacamite and its relationship to spinel. Acta Crystallographica, C42, 12771280.Google Scholar
Pollard, A.M., Thomas, R.G. and Williams, P.A. (1989) Synthesis and stabilities of the basic copper(II) chlorides atacamite, paratacamite and botallackite. Mineralogical Magazine, 53, 557563.CrossRefGoogle Scholar
Schnorrer-Köhler, G. (1987) Die Minerale in den Schlacken des Harzes. Aufschluss, 38, 181197.(in German).Google Scholar
Sheldrick, G.M. (1997a) SHELXS-97, a program for the solution of crystal structures. University of Göttingen, Germany.Google Scholar
Sheldrick, G.M. (19976) SHELXL-97, a program for crystal structure refinement. University of Göttingen, Germany.Google Scholar
Visser, J.W. (1969) A fully automatic program for finding the unit cell from powder data. Journal of Applied Crystallography, 2, 8995.CrossRefGoogle Scholar
Wendel, W., BlaB, G., Miihlbauer, W. and Markl, G. (1999) Hilarion-Plaka-Sounion: Laurion News 1997-1999. Lapis, 24(7), 6467 (in German).Google Scholar
Yvon, K., Jeitschko, W. and Parthé, E. (1977) LAZY PULVERIX, a computer program, for calculating X-ray and neutron diffraction powder patterns. Journal of Applied Crystallography, 10, 7374.CrossRefGoogle Scholar