The Microstructure of Dispersed and Flocculated Samples of Kaolinite, Illite, and Montmorillonite

Samples of kaolinite, illite, and montmorillonite were consolidated from slurries containing chemical dispersant and flocculating agents. The resulting microstructures of the six clays so produced have been studied in the scanning electron microscope, following a preliminary investigation of the problems of sample disturbance during preparation for electron microscopy. It was seen that dispersed and salt-flocculated structures were formed in the illite clays as a result of their high colloidal activity, but that the inactive kaolinite was relatively insensitive to structural effects. The structures of these artificial clays are compatible with the limited results published on undisturbed natural clays. The small size of the montmorillonite particles led to difficulties in the preparation and scanning operations and no conclusions can be drawn for this clay.