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Clay minerals from four different alluvial soils were separated by sedimen — tation and centrifugation. The clay suspensions were then saturated with Mg ions following the removal of iron oxides by sodium dithionite . The samples were subjected to X-Ray , ATP and ATD analyses . The lOA° peak of all samples persisted after heating and glycerol treatment , indicating the presence of illite clays. The l4° peak also remained unchanged and the intensity of lOA° peak increased following this treatments, this may suggest the presence of chlorite and vermiculite in the samples. The results of ATP and ATD analyses also showed a considerable decrease in the weight of the samples in lower temperatures which suggested the presence of vermiculite. The montmorillonite clays were not detected by glycerol treatment. The 3.34A° reveals the presence of quartz. In general the clay minerals ofthe soils studied consist of illite , vermiculite , chlorite and quartz.Some integraded minerals of illite- vermiculite and chlorite- vermiculite might also be present. The ATP and ATb analyses suggested the presence of minute
amounts of kaolinite .