Abstract: A novel aluminum magnesium hydroxy fatty acid compound is disclosed having a general formula, Al.sub.x Mg.sub.y (OH).sub.3x+2y-z R.sub.z.nH.sub.2 O, wherein R is at least one aliphatic monocarboxylic acid group having the formula RCOO.sup.- and comprising from 12 to 22 carbon atoms, and wherein x=2, 2.ltoreq.y.ltoreq.10, z=2, and n is an integer greater than zero. The compound is prepared by a process including placing water and a salt which is one of an alkali metal salt or an ammonium salt of at least one aliphatic monocarboxylic acid having from 12 to 22 carbon atoms in a reactor fitted with heating and stirring means. The salt is dissolved by intensive stirring and by heating to a temperature ranging from 20.degree. to 90.degree. C. to provide a salt solution. The pH of the salt solution in the reactor is maintained at a pH of at least 8 to provide an alkaline solution.