Air pollution control residues from waste incineration have been washed to remove excess chloride and other soluble salts and blended with combinations of soda lime glass and waste electrostatic precipitator dust containing boric oxide from the fibre-glass industry. Homogenous fine powder mixes have been pressed and sintered at temperatures between 900 and 1000 C. The physical properties and microstuctural characteristics of the glass-ceramics formed have been assessed. The results show that it is possible to produce a dense glass-ceramic material containing wollastonite and gehlenite crystalline phases with a hardness of 4.5 GPa. The high density and hardness means that the glass-ceramic may have a potential use in high value construction products.