Abstract: The present invention provides a method for treating clay-bearing aggregates, particularly those used for construction purposes, which involve introducing to clay-bearing aggregates an ion-exchanged polycondensate of dialkylamine and epichlorohydrin having anionic groups comprising both acetate and chloride ionic groups, wherein the acetate is present in an amount of 51-99 percent, and more preferably in the amount of 60-95 percent, based on molar concentration of the anionic groups, whereby chloride ionic groups are minimally present.