Abstract: Aqueous suspensions of ceramic particles in which the particle are coated by a metal oxide sintering aid or metal hydroxide precursor thereto and which have a sufficiently high solids content to produce casting slips which can yield net shape castings are provided. The suspensions are produced by concentrating lower solids content suspensions by crossflow filtration which disrupts hydroxide gels which inherently form by interaction of the coating with water. The resultant highly loaded aqueous suspensions may be used in net shape casting to produce cast bodies of high dimensional stability, high green strength, and with a low incidence of cracking.