Four bone-china body casting-slips were prepared containing either coarse or fine-ground bone in both slop and noodled form and their deflocculation characteristics and casting properties measured. The results have demonstrated that the bodies containing coarse bone cast faster and give firmer casts and in addition noodled bone could give faster casting. For any one body cast firmness depended upon the state of deflocculation of the slip, while casting rate was controlled by the level of dilution. Thixotropy was shown to be unsuitable as a control parameter. 5 refs.