The purpose of this study was to use inorganic wastes to totally replace traditional raw materials for the production of belite-rich clinkers and to investigate the hydration characteristics of the resulting mortars. The produced clinkers were rich in β-dicalcium silicate, and mixed with ordinary Portland cement at various proportions to form blended cements. The hydration of the cement pastes was slowed down by increasing the fraction of belite-rich clinkers. However, the blended cement mortars had comparable compressive strength to the commercial ordinary Portland cement mortar at later curing ages. The results indicate that the blended cements containing up to 40% belite-rich clinkers can still satisfy the compressive strength requirements for Type I Portland cements. The high fraction of belite-rich clinkers in the blended cements produces pastes with longer linear polysilicate anions in the calcium silicate hydrates, which could contribute to the high later-age strength of these blended cement paste mortars.