Density of clay minerals.

Variation in the density of clay minerals with a crystal lattice that swells during hydration is examined. It is demonstrated that greatest intracrystal swelling is attained at the maximum hygroscopic moisture content, involving a reduction to 49% in the density of the solid component. The concept of intracrystal ultramicroporosity n is introduced. The values of n, which must be considered for solution of practical problems, is analyzed. [ABSTRACT FROM AUTHOR]