Hostname: page-component-586b7cd67f-tf8b9 Total loading time: 0 Render date: 2024-11-24T21:34:14.088Z Has data issue: false hasContentIssue false

Crystal structure of mattheddleite: a Pb, S, Si phase with the apatite structure

Published online by Cambridge University Press:  05 July 2018

I. M. Steele*
Affiliation:
Department of Geophysical Sciences, University of Chicago, Chicago IL 60637, USA
J. J. Pluth
Affiliation:
Department of Geophysical Sciences, University of Chicago, Chicago IL 60637, USA Consortium for Advanced Radiation Sources, University of Chicago, Chicago IL 60637, USA Materials Research Science and Engineering Center, University of Chicago, Chicago IL 60637, USA
A. Livingstone
Affiliation:
6, St. Ronan’s Terrace, Innerleithen, Peeblesshire EH44 6RB, UK
*

Abstract

The crystal structure of mattheddleite (Pb5(Si1.5S1.5)O12(Cl0.57OH0.43), P63/m, a = 10.0056(6), c = 7.4960(9) Å) from Leadhills, Scotland has been determined to R = 0.065. The structure is that of apatite where Pb replaces Ca, equal amounts of S and Si replace P and the X anion is OH + Cl. The composition deduced from the structural refinement differs from that of microprobe analyses by giving full occupancy of the tetrahedral site and equal Si and S to preserve charge balance. We conclude that the microprobe analysis is incorrect possibly due to large and inaccurate absorption corrections. For the crystal analysed, the X anion position is zoned from an OH-rich interior to a Cl-rich exterior. The Pb(2) atom is disordered which may be analogous to the disordering of the Ca(2) site in Cl-rich, Ca apatites.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2000

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

Baur, W.H. (1970) Bond length variation and distorted coordination polyhedra in inorganic crystals. Trans. Amer. Crystall. Assoc., 6, 129–55.Google Scholar
Cooper, M.P. and Stanley, C.J. (1991) Famous mineral localities: pyromorphite group minerals from the Caldbeck Fells, Cumbria, England. Mineral. Rec., 22, 105–21.Google Scholar
Cooper, M.P., Green, D.I. and Braithwaite, R.S.W. (1988) The occurrence of mattheddleite in the Caldbeck Fells, Cumbria: a preliminary note. UK J. Mines Mineral., 5, 21.Google Scholar
Dai, Y. and Hughes, J.M. (1989) Crystal-structure refinements of vanadinite and pyromorphite. Canad Mineral., 27, 189–92.Google Scholar
Green, D.I., Rust, S.A. and Mason, J.S. (1996) Classic British Mineral Localities: Frongoch mine, Dyfed. UK J. Mines Mineral., 17, 2938.Google Scholar
Hashimoto, H. and Matsumoto, T. (1998) Structure refinements of two natural pyromorphites, Pb5(PO4)3Cl, and crystal chemistry of chlorapatite group, M5(PO4)3Cl. Zeits. Kristallogr., 213, 585–90.Google Scholar
Hughes, J.M., Cameron, M. and Crowley, K.D. (1989) Structural variations in natural F, OH, and Cl apatites. Amer. Mineral., 74, 870–6.Google Scholar
Hughes, J.M., Cameron, M. and Crowley, K.D. (1990) Crystal structures of natural ternary apatites: solid solution in the Ca5(PO4)3X (X=F,OH,Cl) system. Amer. Mineral., 75, 295304.Google Scholar
Livingstone, A, Ryback, G, Fejer, E.E. and Stanley, C.J. (1987) Mattheddleite, a new mineral of the apatite group from Leadhills, Strathclyde Region. Scott. J. Geol., 23, 18.CrossRefGoogle Scholar
McConnell, D. (1973) Apatite: Its Crystal Structure, Mineralogy, Utilization, and Geologic and Biologic Occurrences. Springer-Verlag, New York and Vienna.CrossRefGoogle Scholar
Moore, R.E. and Eitel, W. (1957) A borosilicate of the apatite group. Naturweiss., 44, 259.CrossRefGoogle Scholar
Rouse, R.C. and Dunn, P.J. (1982) A contribution to the crystal chemistry of ellestadite and the silicate sulfate apatites. Amer. Mineral., 67, 90–6.Google Scholar
Rust, S.A. (1990) Mattheddleite from the Darren mine, Dyfed, Wales. UK J. Mines Mineral., 8, 47–8.Google Scholar
Sudarsanan, K. and Young, R.A. (1978) Structural interactions of F, Cl and OH in apatites. Acta Crystallogr., B34, 1401–7.CrossRefGoogle Scholar