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The cummingtonite problem

Published online by Cambridge University Press:  14 March 2018

W. Layton
Affiliation:
Department of Geology, Durham Colleges in the University of Durham
R. Phillips
Affiliation:
Department of Geology, Durham Colleges in the University of Durham

Summary

An examination of available chemical analyses shows that the anthophyllite and cummingtonite series of amphibole minerals are not isodimorphous. Whilst the anthophyllites are truly lime-free amphiboles, small amounts of calcium are essential to stabilize the monoclinic lattice of cummingtonites, which should be regarded as lime-poor amphiboles, analogous to the lime-poor pyroxenes. The existence of synthetic clino-anthophyllites is considered.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1960

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