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HIGH resolution electron mierographic techniques have been employed for surveying the size and shape distributions of kaolinite particles, both plates and stacks, from wellcrystallized Georgia deposits.Both size and shape follow typical, positively-skewed, frequency distributions. Particle thicknesses among plates appear quantized, dominantly as hoxalaminae and subordinately as trilaminae of the basic c-axis dimension in the unit cell. Specimens subjected to severe shear and attrition show intermediate values of thickness, i.e. 3~ ~ 1 and 3n + 2. Profile studies on kaolinite stacks reval integral platelet units whose distribution in thickness corresponds to that of individual plates.Energy calculations for fracture (cleavage ]1 to c-axis) and delamination (cleavage .[c-axis) processes indicate that hydrokinotic cleavage in nature should result in particles having an aspect ratio distribution peaking near 6 : 1. The dominance of stacks above 10/~ is suggestive of in situ weathering. Experimental shear measurements correlate well with these proposals.Sedimentation studies with clays of various shapes and distributions were performed in a variety of aqueous media, including sea water. Sediment volume data, microscopic observations, and theoretical packing calculations are compared with the several mechanisms proposed for plate-stack genesis.

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Abstract-An investigation of the reaction between amines and hydrogen kaolinites having a broad range of crystallinites and particle sizes has been made. Aqueous and non-aqueous adsorption isotherms, conductivity titrations, rheological measurements and sediment volume studies give strong evidence that edge sites are dominantly involved in the reaction and basal surfaces remain essentially unaltered. The acid-base reaction produces a localized adduct rather than an ionized, protonated amine. The amine-hydrate adduct adsorbs with greatly modified geometry.

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