The body is Plainsman L215 (bisque fired at cone 06). The glaze is G2931K. There is good reason to glaze fire to cone 03 instead of 04. Although these commercial underglazes work the same the clay fired at cone 03 is stronger and a deeper red color. But best of all, the glaze is more transparent (because it has fewer micro-bubbles suspended in the glass). Cone 03 is also more tolerant of getting the glaze on too thick, at 04 it will turn completely milky.
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