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A Columnar Growth of Dendritic Pyroxene

Published online by Cambridge University Press:  01 May 2009

J. Preston
Affiliation:
Dept. of Geology, The Queen's University, Belfast.

Abstract

One of the internal contacts of a doleritic intrusion, Co. Donegal, is lined with large augite dendrites. The habit is revealed by parting on a median zone of chlorite which is regarded as an altered exsolution feature. It is suggested that an initial platy dendrite grew, in response to undercooling, as a metastable phase with the composition and structure of a high-calcic pigeonite. A later overgrowth of augite preserved the delicate crystal against destruction.

Type
Articles
Copyright
Copyright © Cambridge University Press 1966

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