Abstract: According to the present invention, there is provided a wet accelerator for use in the manufacture of a gypsum product, said wet accelerator comprising water, particles of calcium sulphate dihydrate and a stabiliser. Additionally, a method of preparing a wet accelerator and a method of producing a gypsum product are described.

Abstract: Process for manufacturing a product, including the following successive steps: a) mixing raw materials to form a starting feedstock; b) melting the starting feedstock so as to form a molten liquid; c) solidifying the molten liquid so as to obtain a fused product comprising crystals linked by a glassy phase; and d) crystallization heat treatment of the glassy phase of said fused product, in which the composition of the starting feedstock is adapted in order to manufacture a product having the following chemical composition, as weight percentages based on the oxides, and for a total of 100%: 40%?(ZrO2+HfO2)?94%; 4%<CeO2<31%; 0%?Y2O3; 0%?Al2O3; 2%?SiO2; 0%?MgO; 0%?TiO2; and other oxides?1%.