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Al-Cr substitution in peraluminous sapphirines from the Bjørnesund area, Fiskenaesset region, southern West Greenland

Published online by Cambridge University Press:  05 July 2018

C. R. L. Friend*
Affiliation:
Department of Geology and Physical Sciences, Oxford Polytechnic, Headington, Oxford, OX3 0BP

Abstract

Cr-rich Mg-sapphirines, which are more aluminous in composition than R2+:R3+:Si of 7:9:3 and are therefore considered to be peraluminous, are shown to have an inverse linear relationship between octahedrally co-ordinated Cr and Al. This balanced substitution, which has not previously been described, may be used to explain the major chemical variations exhibited in the described minerals. Since the peraluminous Cr-rich sapphirines are idioblastic it is suggested that they are stable members of the assemblages within which they occur. Peraluminous sapphirine is usually considered to be metastable but in this instance it is possible that chromium may assist in stabilizing its development.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1982

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References

Bøgglid, O. B. (1953) Meddels. Grønland 149, 3, 192–4.Google Scholar
Bridgwater, D., Keto, L., McGregor, B. R., and Myers, J. S. (1976) In Geology of Greenland (Escher, A., and Watt, W. S., eds.), GGU, Copenhagen, 1875.Google Scholar
Cameron, W. E. (1976) Geol. Mag. 113, 497514.CrossRefGoogle Scholar
Deer, W. A., Howie, R. A., and Zussman, J. (1978) Rock-Formina Minerals, Vol. 2a. Longmans, London.Google Scholar
Ellis, D. J., Sheraton, J. W., England, R. N., and Dallwitz, W. B. (1980) Contrib. Mineral. Petrol. 72, 123–43.CrossRefGoogle Scholar
Friend, C. R. L., and Hughes, D. J. (1977) Earth Planet. Sci. Lett. 36, 157–67.CrossRefGoogle Scholar
Friend, C. R. L., and Hughes, D. J. (1981) Rapp. Grønlands geol. Unders. 105, 41-t.Google Scholar
[Giesecke, K. L.] (1910) Meddels. Grønland, 35.Google Scholar
Herd, R. K. (1972) Univ. London unpubl. Ph.D. thesis.Google Scholar
Herd, R. K. (1973) Rapp. Grønlands geol. Unders. 51, 6571.Google Scholar
Higgins, J. B., Ribbe, P. H., and Herd, R. K. (1979) Contrib. Mineral. Petrol. 68, 349–56.CrossRefGoogle Scholar
Leake, B. E. (1978) Mineral. Maa. 42, 533–63.CrossRefGoogle Scholar
Meyer, H. O. A., and Brookins, D. G. (1976) Am. Mineral 61, 1194–202.Google Scholar
Moore, P. B. (1969) Ibid. 54, 3149.Google Scholar
Ramberg, H. (1948) Meddels. Grønland, 142, 5, 132.Google Scholar
Schreyer, W., and Abraham, K. (1975) Mineral. Mao. 40, 171–80.CrossRefGoogle Scholar
Schreyer, W., and Abraham, K. (1976) Contrib. Mineral. Petrol. 54, 109–26.CrossRefGoogle Scholar
Walton, B. J. (1973) Rapp. Grønlands geol. Unders. 51, 60–4.Google Scholar