Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-28T18:20:51.512Z Has data issue: false hasContentIssue false

Electron Microscopy of Clay Surfaces

Published online by Cambridge University Press:  01 January 2024

Thomas F. Bates
Affiliation:
The Pennsylvania State University, USA
J. J. Comer
Affiliation:
The Pennsylvania State University, USA
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Improvements in replica techniques have made possible the high magnification study of textural characteristics and surface features of clay aggregrates found either in nature or in the laboratory. The most successful method of sample preparation involves pre-shadowing the specimen with platinum and backing this with a layer of carbon prior to removal of the clay with a suitable solvent.

Data on orientation and packing of clay particles are readily obtained. The method is useful to investigate clays in which the characteristic morphology is easily affected by environmental conditions or by sample preparation for other methods of study.

Replicas of kaolinite indicate that many of the pseudohexagonal plates seen in electron micrographs are cleavage fragments. Investigations of halloysite (4 H2O) using this technique prove that the tubes exist as such in the bulk clay. Striations on montmorillonite flakes that intersect at an angle of sixty degrees suggest a degree of morphological crystallinity that is apparently destroyed when the material is dispersed prior to study in the electron microscope. Replicas of dickite, attapulgite and weathered feldspar also show features that have not heretofore been seen in electron micrographs.

Type
Article
Copyright
Copyright © The Clay Minerals Society 1954

References

Bates, T. F., Hildebrand, F. A., and Swineford, A. (1950) Morphology and structure of endellite and halloysite: Am. Mineral., vol. 35, pp. 463484.Google Scholar
Bradley, D. E. (1954) Evaporated carbon films for use in electron microscopy: British J. Applied Phys., vol. 5, pp. 6566.CrossRefGoogle Scholar
Comer, J. J., and Turley, J. W. (1955) Replica studies of bulk clays: J. Applied Phys., vol. 26, pp. 346350.CrossRefGoogle Scholar
Gerould, C. H. (1947) Preparation and uses of silica replicas in electron microscopy: J. Applied Phys., vol. 18, p. 333.CrossRefGoogle Scholar
Hamm, F. A., and Comer, J. J. (1948) Replica studies of dyed nylon: Anal. Chem., vol. 20, pp. 861870.CrossRefGoogle Scholar
Hast, N. (1947) Structure of clay: Nature, vol. 159, p. 354.CrossRefGoogle Scholar
Sand, L. B., and Comer, J. J. (1955) A study in morphology by electron diffraction: Paper presented at the Third National Clay Minerals Conference, Houston, Texas.Google Scholar
Schaefer, V. V., and Harker, D. (1942) Surface replicas for use in the electron microscope: J. Applied Phys., vol. 13, p. 427.CrossRefGoogle Scholar
Williams, R. C., and Wyckoff, R. W. G. (1946) Applications of metallic shadow casting to microscopy: J. Applied Phys., vol. 17, p. 23.CrossRefGoogle Scholar
Williams, R. G, and Wyckoff, R. W. G. (1945) Electron shadow micrography of the tobacco mosaic virus protein: Science, vol. 101, p. 594.CrossRefGoogle ScholarPubMed