Differentiation between Endellite-Halloysite and Kaolinite by Treatment with Potassium Acetate and Ethylene Glycol

W. D. Miller1 and W. D. Keller
Department of Geology, University of Missouri, Columbia, Missouri
1 Present address, Dept. of Geology, Texas Tech. Inst., Lubbock, Texas.

Abstract: Halloysite and endellite yield 10 Å basal spacings after grinding with potassium acetate (using a modification of Wada's procedure) and washing with water and ethylene glycol, whereas the basal spacing of kaolinite, similarly treated, remains at 7 Å. The technique applies satisfactorily to sedimentary and hydrothermal halloysites, various commercial kaolins, ball clays, flint and plastic fire clays, and artificially prepared mixtures of halloysite and kaolinite. Similar responses to the treatment by both laboratory-dehydrated endellite (thereby collapsed to 7 Å) and naturally occurring halloysite add support to the concept that endellite is a progenitor of halloysite.

Clays and Clay Minerals; 1961 v. 10; no. 1; p. 244-253; DOI: 10.1346/CCMN.1961.0100120
© 1961, The Clay Minerals Society
Clay Minerals Society (www.clays.org)