Critical Study of the Differential Thermal Method for the Identification of the Clay Minerals*

A bstract An apparatus is described for studying clay minerals by the differential thermal method, which has some advantages over previous types of apparatus. Thermal curves are given for many of the pure clay minerals for use as standards of identification. The use of this method quantitatively for the determination of the relative amounts of clay minerals in a natural clay is discussed, and examples are given for a number of high alumina clays.