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Some unusual alkali-felspars in the Central Australian charnockitic rocks

Published online by Cambridge University Press:  14 March 2018

Allan F. Wilson*
Affiliation:
University of Western Australia; formally of Department of Geology, University of Adelaide, South Australia

Extract

During a universal stage investigation of the pegmatitic felspars in the Central Australian charnockites, several alkali-felspars were found which, according to the stereograrms published by Emmons (3, pl. 12), should have been near ' anorthoclase' in composition. This identification, based purely on optical properties, was questioned in the first instance because of the absence of other evidence for a soda-rich suite of minerals in these apparently potassic pegmatites. Two felspars which suggested a high soda-content were chemically analysed. Neither proved to be notably high in soda.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1950

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References

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