Non-oxide refractory foams, possessing controlled permeability and uniformity, are prepared by impregnating an organic polymer foam material with a fluid, particulate slurry of a first refractory material, drying, applying to the dried, impregnated material a second refractory material which has a lower melting point than the first refractory material and thereafter heating, at a temperature sufficient to cause melt infiltration of the second refractory material into the impregnated material, thus producing inert and dimensionally stable composite refractory foams having broad utility as particulate filters or carriers.