A convenient process for making builder material which has substantially improved performance and is significantly less expensive than previous builders is provided. The builder material has improved performance in that it unexpectedly has a high calcium ion exchange capacity and rate, and is easy to handle, process and disperse in washing solutions. In its broadest aspect, the invention is directed to a process involving converting starting materials (via any means including but not limited to heating and precipitating) to a builder material having at least one crystalline microstructure including a carbonate anion, calcium cation and at least one water-soluble cation. The microstructure should have a sufficient number of anions and cations so as to be "balanced" or "neutral" in charge.