An Occurrence of Phlogopite and Its Transformation to Vermiculite by Weathering

W. W. Smith Aitken
The Macaulay Institute for Soil Research, Aberdeen, Scotland

Summary: The characteristics of a phlogopite and its weathering product, vermiculite, have been studied by X-ray, infra-red, electron-microscope, and chemical methods. Inclusions within these minerals have been identified as thin films rich in iron oxide (which impart a schiller effect), spinel (which may exist in a preferred orientation), and serpentine. The orientation relationship between the fresh mica and its weathering product has been established by single-crystal methods. The mechanism of transformation from a 1-layer to a 2-layer polytype is discussed.

Mineralogical Magazine; March 1965 v. 35; no. 269; p. 151-164; DOI: 10.1180/minmag.1965.035.269.18
© 1965, The Mineralogical Society
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