Extended use zirconium silicate compositions and methods of use thereof

A method of making zirconium silicate comprising:

• adding sodium hydroxide and water to a reactor to form a first mixture;
• adding colloidal silica to the first mixture in the reactor and agitating at a first agitation rate to obtain a second mixture;
• and,
• reducing the agitation rate to a second agitation rate that is lower than the first agitation rate and adding zirconium acetate to the second mixture, thereby reacting the colloidal silica with zirconium acetate to form zirconium silicate, wherein the zirconium silicate has a lead content of less than 0.6 ppm.