Formation of spurrite, Ca5(SiO4)2CO3

Abstract The conditions leading to spurrite formation in the kiln have been simulated by laboratory studies, using reagent-grade reactants. Fluorine, and to a lesser extent chlorine, (F −, Cl−) are effective mineralizers, but direct synthesis of spurrite without mineralizers is only achieved if Ca3SiO5 is used as a reactant. Both types of reaction are considered to be feasible in kilns, with kiln dust being the likely source of transported Ca3SiO5. Water vapour introduced with CO2 is not effective in enhancing spurrite formation.