Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-27T07:12:13.156Z Has data issue: false hasContentIssue false

The crystal structure of wardite1

Published online by Cambridge University Press:  05 July 2018

L. Fanfani
Affiliation:
Istituto di Mineralogia, Università di Perugia, Italy
A. Nunzi
Affiliation:
Istituto di Mineralogia, Università di Perugia, Italy
P. F. Zanazzi
Affiliation:
Istituto di Mineralogia, Università di Perugia, Italy

Summary

Wardite, NaAl3(OH)4(PO4)2. 2H2O, has a = 7·03 Å, c = 19·04 Å; space group P41212 or P43212. Its crystal structure was solved by a three-dimensional Patterson function computed using intensity data photographically collected by the Weissenberg method, and refined by successive Fourier maps and least-squares cycles to a R index 0·062 for 316 independent observed reflections.

The wardite structure is formed by layers of Al and Na coordination polyhedra sharing vertices and edges. These sheets, parallel to the a axes, are connected to each other in the c direction by PO4 tetrahedra and H-bonds. This structural feature accounts for the perfect {001} cleavage of wardite and explains the change that occurs in lattice parameters when Al is substituted by Fe in avelinoite. The relationships with the minerals of the trigonal families of crandallite, woodhouseite, and jarosite are also discussed.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1970

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

Albano, (V.), Bellon, (P. L.), Pompa, (F.), and Scatturin, (G.), 1963. La Ricerca Scientifica, 3A, 1067.Google Scholar
Brophy, (G. P.), Scott, (E. A.), and Snellgrove, (R.), 1962. Amer. Min. 47, 112.Google Scholar
Capdecomme, (L.) and Pulou, (R.), 1954. Compt. Rend. Aead. Sei. Paris, 239, 288.Google Scholar
Davison, (J. M.), 1896. Amer. Journ. Sci., ser. 3, 2, 154.CrossRefGoogle Scholar
Hamilton, (W. C.), 1959. Acta Cryst. 12, 609.CrossRefGoogle Scholar
Heritsch, (H.), 1955. Tsehermaks Min. Petr. Mitt., ser. 3, 5, 246.CrossRefGoogle Scholar
Hurlbut, (C. S.), 1952. Amer. Min. 37, 849.Google Scholar
International Tables for X-Ray Crystallography, 1962, 3, 202, Birmingham (Kynoch Press).Google Scholar
Larsen, (E. S.), 1942. Amer. Min. 27, 281.Google Scholar
Larsen, (E. S.), and Shannon, (E. V.), 1930. Ibid. 15, 307.Google Scholar
Lindberg, (M. L.), 1957. Ibid. 42, 204.Google Scholar
Owens, (J. P.), Altschuler, (Z. S.), and Berman, (R.), 1960. Ibid. 45, 547.Google Scholar
Pabst, (A.), 1947. Ibid. 32, 16.CrossRefGoogle Scholar
Papike, (J. J.) and Clark, (J. R.), 1968. Ibid. 53, 1156.Google Scholar
Pough, (F. H.), 1937. [Amer. Mus. Nov., no. 932, P. 1]; in Amer. Min., 1942, 27, 293.Google Scholar
Prewitt, (C. T.) and Burnham, (C. W.), 1966. Amer. Min. 51, 956.Google Scholar
Stewart, (J. M.), 1964. Technical Report TR-64-6, Univ. of Maryland. Google Scholar