The lower black glaze is a base coat G3914A Alberta Slip base (with 4% Mason 6600 stain). The white overglaze is G3912A with tin oxide opacifier. Normally I would fire this combination at cone 6, but this time I tried cone 8. It is a little high for this clay body, but the glaze variegation is better.
A mottled glaze created by double-layering glazes of different melt fluidity and color
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