 This research examined the use of recycled slag and fly ash in combination with calcium sulfate to create ternary mixtures for use in construction applications. The mixtures were tested for setting times and mechanical properties and compared to traditional Portland cement, calcium aluminate cement and calcium sulfate mixtures. The results showed that the addition of calcium sulfate increased the strength of the mixtures while reducing the setting time. Additionally, the presence of calcium sulfate caused the formation of a tringeite, which is a hydrated compound formed by the reaction between calcium sulfate and calcium silicate hydrate. This finding suggests that calcium sulfate can be used as a substitute for natural potsalins in order to reduce the amount of waste produced during construction projects. This article was authored by David Torrance-Martin, Lucia J. Fernandez-Corosco and Maria Teresa Blanco-Varela.