Anauxite and Kaolinite Structures Identical

S. W. Bailey and R. B. Langston
Department of Geology and Geophysics, University of Wisconsin, Madison, Wisc. 53706
Department of Materials Science and Engineering, University of California, Berkeley, Calif. 94720

Abstract: Single crystal X-ray diffraction patterns reveal that the structure of selected anauxite crystals is the same as the structure of macroscopic kaolinite crystals. Anauxite and kaolinite crystals are intergrowths on a domain scale of units in pseudotwin orientations. Individual domains in anauxite have the triclinic geometry of kaolinite, and give X-ray reflections that compare closely in intensity with those calculated from the atomic parameters of kaolinite. Large crushed crystals of anauxite give powder patterns identical with that of kaolinite. Because it has been shown recently that the chemical composition of anauxite is also identical with that of kaolinite, it is recommended that the term “anauxite” no longer be used.

Clays and Clay Minerals; October 1969 v. 17; no. 4; p. 241-243; DOI: 10.1346/CCMN.1969.0170407
© 1969, The Clay Minerals Society
Clay Minerals Society (www.clays.org)