The best Opaque White for overglaze painting that will cover even black. Mix as usual with your regular mixing and painting medium: Open – Always Open Medium or Fast Drying: Pollyanna Medium for 2 ideas. Fire any overglaze temperature from Cone .014 – .018. For a Water Based Medium, use OJ2 Josephine Water Medium Fast Drying, or, OR4 Josephine Water Medium Slow Drying.
Fire to entire overglaze firing temperatures: HOT: Cone .014, 870 C, 1596 F; to COOL: Cone .019, 723 C, 1333F.