The pursuit of new raw materials for the design and manufacture of more sustainable cements has aroused considerable technological interest in the cement industry, which is currently under extreme political and social pressure to reduce the huge volume of its CO2 emissions.The present paper reports on research into the pozzolanicity of sanitary ware industry waste and the viability of including certain percentages of such waste as an addition with a view to more sustainable type II, IV and V cements.The waste was characterised chemically,mineralogically and microstructurally prior to exposure to a saturated lime solution for 1 and 28 days.The pozzolanicity of the products was determined and the samples were analysed with different experimental techniques.Pozzolanic activity was lower in this waste than in silica fume but higher than in other traditional additions such as fly ash and natural pozzolans.