This glaze looks pretty cool and possible to do. Maybe put a thin line of wax resist under the outside line so it really pools relatively evenly. If the glaze is heavy enough then it should melt over the line and that would look even more awesome.
ardith one, Canadian Pottery and Crafts Newsletter: May 2010
Terri Kern how to apply underglazes. She uses a red clay and then applies yellow underglaze on top of earthenware.
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Vessel of light
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