The effect of additives on the growth of silver particles in a lead borosilicate glass was studied. Growth of silver particles was expressed by the Ostwald ripening theory and controlled by diffusion. Addition of palladium retarded the growth of silver particles. This is attributed to the reduced activity of silver caused by the formation of silver–palladium solid solutions. Addition of ruthenium dioxide promoted the growth, whereas addition of tin dioxide had almost no effect on the growth rate. A “solubility parameter” was introduced to evaluate the temperature dependence of solubility of silver in glass, and the effect of additives has been discussed. Association of diffusion species has been proposed as a possible factor responsible for the temperature dependence of the solubility para