Abstract: A foundry coating composition for moulds and cores, a process for preparing coated foundry moulds and cores, and coated moulds and cores obtainable by the process. The foundry coating composition comprises a liquid carrier; a binder; and a particulate refractory filler. The particulate refractory filler comprises a first (relatively coarse) fraction having a particle size of d>38 ?m and a second (relatively fine) fraction having a particle size of d<38 ?m. No more than 10% of the total particulate refractory filler has a particle size of 38 ?m<d<53 ?m and no more than 50% of the second (relatively fine) fraction is constituted by calcined kaolin. The foundry coating composition is applied to moulds and cores to assist in the removal of the casting from the mould and prevention of casting defects.