A method of making an antiperspirant active composition and the use of a heating step at elevated temperature to convert Al13 polyhydroxyoxoaluminum cations in the species detectable by 27Al NMR within an aqueous aluminum salt solution into Al30 polyhydroxyoxoaluminum cations in the species detectable by 27Al NMR without increasing a SEC Peak 3 area in the SEC chromatogram of the aluminum salt.
