Clay Sols versus Clay Gels: Biological Activities Compared

Clay gels were prepared by extrusion of sodium-Wyoming bentonite pastes through a small orifice. Clay sols were prepared from the gels by rapping on the laboratory bench for disturbance. Lettuce seeds germinated faster, microbes generated more heat, and corn seedlings absorbed more (22)Na in the sols than in the gels. These differences in biological activity are attributable to changes in water properties and ion activities that accompany transformation from gelsol.