On the right is L213, a body made using Taxas talc and Kentucky ball clay. On the left is L3778H, a translucent porcelain made using Grolleg kaolin, Nepheline syenite and silica. It normally vitrifies at cone 6 but we don’t need vitrification here because this is for artware, just like L213. At cone 04 these two have similar porosities and fired strengths. The glaze is G1916QL1, a crystal clear transparent glaze. The glaze does craze after a few days on the porcelain. Increasing the firing temperature to cone 03 extends that time to 3 weeks. Cone 02 may extend it further. Other options to improve glaze frit would be to increase the silica content in the body (at the expense of kaolin) and further reduce the thermal expansion of the glaze.
Potters know artware as pottery firing at low temperatures with brightly coloured glazes and decorated using decals, underglazes, lustres, etc.