Hostname: page-component-7bb8b95d7b-pwrkn Total loading time: 0 Render date: 2024-09-20T12:45:19.042Z Has data issue: false hasContentIssue false
  • English
  • Français

The crystal chemistry of the apatites

Published online by Cambridge University Press:  14 March 2018

A. G. Cockbain
A. G. Cockbain*
Affiliation:
Allen Clark Research Centre, The Plessey Company Limited, Caswell, Towcester, Northamptonshire
Get access Rights & Permissions [Opens in a new window]

Summary

The compositions of more than eighty synthetic members of the apatite group with the general formula A10(XO4)6Z2 have been used as a basis for classifying the apatites into three groups. The ratios of the mean sizes of the ‘A’ ions to those of the ‘X’ ions for all these compositions lie between the limits of 1·89 and 4·43. A discontinuity occurs between ratios of 2·50 and 2·60 and probably another between 3·25 and 3·35, and these discontinuities provide a structural basis for the division into the three groups. The groups are named after well-known mineral species occurring in each group, i.e. the vanadinite-svabites with an A : X ratio less than 2·5, the apatite-mimetites between 2·60 and 3·25, and the pyromorphites with A : X greater than 3·25.

Type
Research Article
Information
Mineralogical magazine and journal of the Mineralogical Society , Volume 36 , Issue 281 , March 1968 , pp. 654 - 660
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1968

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

Adler, (H. H.), 1964. Amer. Min., vol. 49, p. 1002.Google Scholar
Baker, (W. E.), 1966. Ibid., vol. 51, p. 1712.Google Scholar
Cockbain, (A. G.) and Smith, (G. V.), 1967. Min. Mag. vol. 36, p. 411.Google Scholar
Geller, (R. F.) and Bunting, (E. N.), 1939. Jour. Res. Nat. Bur. Standards, vol. 23, p. 281.Google Scholar
Montel, (G.), 1958. Ann. Chim. (Paris), vol. 13, p. 313.Google Scholar
Moore, (R. E.) and Eitel, (W.), 1957. Naturwiss., vol. 44, p. 259.Google Scholar
Posner, (A. S.), Stutman, (J. M.), and Lippincott, (E. R.), 1960. Nature, vol. 188, p. 486.Google Scholar
Strens, (R. G. J.), 1965. Min. Mag., vol. 35, p. 547.Google Scholar
Trömel, (G.) and Eitel, (W.), 1957. Zeits. Krist., vol. 109, p. 231.CrossRefGoogle Scholar
Wyckoff, (R. W. G.), 1965. ‘Crystal Structures’, vol. 3, 2nd edn (John Wiley and Sons, New York).Google Scholar