(O) Opalescent Although AMACO® Opalescent Glazes may be used on any AMACO® clay, they develop their greatest opalescence and most interesting textures when applied over red burning AMACO® Sedona Red Clay No. 67. The AMACO® Opalescent Glazes have a high gloss finish when fired. Best results are achieved with three or four applications of glaze. On textured ware, the glaze flows thin on relief and thick in incised areas, giving an added dimension on the surface. •Best over Red clay or colored Underglazes •Break and Pool Over Texture •Cone 05 Sapphire Blue is an active, flowing low-fire glaze that breaks clear over texture and pools a rich electric blue where thick. Because of its tendency to break and expose the clay body beneath, this glaze looks stunning over 67-M (Sedona) and over textured ware that has been painted with underglaze. Tableware producers must test all finished ware to establish dinnerware status, due to possible variations in firing temperature and contamination.