SW-250 White OpalCone 6 oxidation: White Opal forms a clear to milky white gloss surface. One coat produces the clearest finish; subsequent layering increases the incidence of a white precipitate forming. Prominent white to bluish white colors will emerge where the glaze pools and gathers around surface texture. Cone 10 reduction: White variation lessens leaving a transparent gloss with white pooling. TIP: White coloration is more visible on darker clay bodies (Buff,