White Star CN401 An all-purpose casting slip with excellent plasticity. This casting slip clay produces strong greenware and fires white. Works well with most low fire glazes. Fire Cone 06-04. Characteristics Cone: 06 Firing Color: Oxidation: White - Reduction: N/A Avg. Shrinkage 2±%: 6% Avg. Water Absorption 1±%: 19% COE x 10-6: 8.65