THE INTERIOR STRUCTURE OF SPHERICAL HALLOYSITE PARTICLES

Abstract

The interior structure of spherical halloysite particles in two weathered pumice samples was examined by electron microscopy in combination with potassium acetate treatment for a gentle breaking up of the spherical particles and by dissolution analysis with oxalate-oxalic acid-difference infra-red spectroscopy. The results indicated concentric and discontinuous stackings of kaolin unit layers and a cavity in the core. Allophane was not detected in any substantial amount, but some defect structure intermediate between allophane and halloysite was suspected in the spherical particles. An outward, layer by layer growth of the spherical halloysite particles was suggested.