A process for the preparation of amorphous aluminum phosphate or polyphosphate-based pigment by reacting aluminum phosphate and sodium aluminate is provided. The amorphous aluminum phosphate or polyphosphate is characterized by a skeletal density of less than 2.50 grams per cubic centimeter and a phosphorus to aluminum mole ratio of greater than 0.8. In one embodiment, the composition is useful in paints as a substitute for titanium dioxide.