The instant invention is a cure system for halogenated elastomer compositions, a curable halogenated elastomer composition, and a method for curing a halogenated elastomer composition. The cure system for halogenated elastomer compositions includes a polymercapto crosslinking agent, an inorganic base, and a hydrated salt selected from the group consisting of lithium citrate, trilithium citrate pentahydrate, trilithium citrate tetrahydrate, and monolithium dihydrogen citrate monohydrate. The curable halogenated elastomer composition includes a chlorinated elastomer, and a cure system including a polymercapto crosslinking agent, an inorganic base, and a hydrated salt selected from the group consisting of lithium citrate, trilithium citrate pentahydrate, trilithium citrate tetrahydrate, and monolithium dihydrogen citrate monohydrate. Furthermore, the method for curing a halogenated elastomer composition includes the following steps: (1) providing a chlorinated elastomer composition; (2) providing a cure system composition including a polymercapto crosslinking agent, an inorganic base, and a hydrated salt selected from the group consisting of lithium citrate, trilithium citrate pentahydrate, trilithium citrate tetrahydrate, and monolithium dihydrogen citrate monohydrate; (3) uniformly blending the cure system into the chlorinated elastomer composition; (4) thereby forming a curable chlorinated elastomer composition; (5) subjecting the curable chlorinated elastomer composition to heat or heat and pressure; and (6) thereby curing the curable chlorinated elastomer composition.