Abstract: A dispersant system for formulating stable non-aqueous siliceous particulate slurries, comprising a vehicle comprising a liquid ester, and a dispersant comprising an alkoxylated aminoalcohol and organophosphate ester. Siliceous particulate slurries in accordance with the present invention can include slurries containing siliceous ceramic particulate (i.e., silicon nitride, silicon carbide, silica, and silicon metal powders partially oxidized by air exposure). A wide variety of linear and cyclic organic esters can be used as a vehicle component, including lactones. The alkoxylated aininoalcohol is typically an ethoxylated aminoethanol oligomer. A wide variety of aromatic and nonaromatic organophosphate ester compounds can be used for the second dispersant component.