Density and structure of allophane

Abstract

Abstract The densities of two allophane samples measured by displacement with water were 2·72–2·78 g/cm 3 , while those measured by a float-sink test in CH 3 OH-, CH 3 COCH 3 -, C 6 H 6 - and CCl 4 -C 2 H 2 Br 4 mixtures were 1·84, 1·94–1·98, 2·35 and 2·35–2·39 g/cm 3 , respectively. The results of the density determinations for montmorillonite, kaolinite, halloysite, imogolite and volcanic glass are also reported. The data were interpreted in terms of the accessibility of the displacement liquids to void spaces within and between the layers or ‘structure units’ of the minerals and a model of the ‘structure units’ of allophane is proposed.