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An Occurrence of Detrital Diaspore in South Wales

Published online by Cambridge University Press:  01 May 2009

J. C. Griffiths  and
Alan Stuart
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Extract

During the course of a petrological investigation by one of us (J. C. G.) of the glacial deposits in South-West Wales, samples from a sandy boulder clay at Ludchurch in South-East Pembrokeshire were found to contain abundant grains of a platy colourless mineral with a specific gravity greater than 2·9, a perfect pinacoidal cleavage and high double refraction. This was ultimately diagnosed as diaspore, with which were associated various iron ores, zircon, rutile, chlorite, various tourmalines (brown, green, and pink being the commonest), pyroxenes, amphiboles, staurolite, kyanite, brookite, anatase, topaz, garnet, apatite, muscovite, and andalusite, an assemblage typical of the Irish Sea Drift of this district. A search through the literature for a description of detrital diaspore showed that there did not appear to have been published any detailed description with figures of the detrital forms.

Type
Articles
Information
Geological Magazine , Volume 77 , Issue 1 , February 1940 , pp. 74 - 76
Copyright
Copyright © Cambridge University Press 1940

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References

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