Hostname: page-component-848d4c4894-4hhp2 Total loading time: 0 Render date: 2024-06-09T11:13:04.960Z Has data issue: false hasContentIssue false
  • English
  • Français

An Occurrence of Detrital Diaspore in South Wales

Published online by Cambridge University Press:  01 May 2009

J. C. Griffiths  and
Alan Stuart
Get access Rights & Permissions [Opens in a new window]

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Berg, E. L. An Occurrence of Diaspore in Quartzite. Amer. Min., xxii, 1937, 997.Google Scholar
2. Boswell, P. G. H. Some Aspects of the Petrology of Sedimentary Rocks. Proc. Liverpool Geol. Soc., xiii, pt. iv, 1923, 268.Google Scholar
3. Branner, J. C. The Minerals Associated with Diamonds and Carbonados in the State of Bahia, Brazil. Amer. Journ. Sci., xxxi, No. 186, 1911, 480.Google Scholar
4. Chelussi, I. Osservazione petrografiche sopra alcune sabbie della costa Toscana e della pianura grossetana. Boll. Soc. geol. ital., xxix, 1910, 211.Google Scholar
5. Damour, A. Nouvelles recherches sur les sables diamantiferes. Bull. Soc. geol. France, xiii, 1856, 542.Google Scholar
6. Dana, E. S. A System of Mineralogy, 6th edn., 1914, 246.Google Scholar
7. Emmons, R. C. The Double Dispersion Method of Mineral Determination. Amer. Min., xiii, 1928, 504.Google Scholar
8. Iddings, J. P. Rock Minerals, 2nd edn., 1911, 570.Google Scholar
9. Kerr, P. F. The Occurrence of Andalusite and related minerals at White Mountain, California. Econ. Geol., xxvii, 1932, 626.Google Scholar
10. Ricciardi, L. Ricerche sulle sabbie delle coste adriatiche sulle cause dell' interrimento dell Porto di Bari. Atti. Soc. ital. Sci. nat., xxxiii, 1890, 41.Google Scholar
11. Ries, H., Bayley, W. S., and others. High-grade Clays of the Eastern United States. U.S. Geol. Surv., Bull. 708, 1922, 299.Google Scholar
12. Somers, R. E. Microscopic examination of Clays. Journ. Washington Acad. Sci., ix, 1919, 113.Google Scholar
13. Tucan, F. Terra Rosa, deren Natur und Entstehung. N.J.f. Min., xxxiv, 1912, 401.Google Scholar
14. Uzielli, G. Sopra lo zircone della Costa Terrana. Atti. R. Accad. Lincei, iii, 1875–1876, 862.Google Scholar
15. Winchell, A. N. Elements of Optical Mineralogy. 2nd edn., part ii, 1931. 45.Google Scholar
16. Yoshiki, B. Diaspore from Shokozan. Proc. Imp. Acad. Tokyo, ix, 1933, 109CrossRefGoogle Scholar