Scan Electron Micrographs of Kaolins Collected from Diverse Origins—III. Influence of Parent Material on Flint Clays and Flint-Like Clays

W. D. Keller
Department of Geology, University of Missouri-Columbia, Columbia, MO, U.S.A.

Abstract: The nature of the parent material from which flint clay or flint-like clay is derived may modify the texture of the clay as observed by SEM. Flint clays occurring in Pennsylvanian-age swamp basins into which were transported residues weathered from sedimentary country rock exhibit a texture of interlocked kaolin pockets and sheaves. On the other hand, flint clay or flint-like clay derived by weathering of volcanic ash exhibits a texture resembling, on a micro-scale, the scalloped, “oak-leaf” pattern of montmorillonite. The interpretation is that an expanding clay having a transitional role between the ash and the kaolinite is the donor source of the micro-scalloped pattern inherited by kaolinite. X-ray powder diffractograms of the clays support the interpretation.

Clays and Clay Minerals; October 1976 v. 24; no. 5; p. 262-264; DOI: 10.1346/CCMN.1976.0240508
© 1976, The Clay Minerals Society
Clay Minerals Society (www.clays.org)