A high Soda (Na2O) Frit with a high expansion.
Used for Copper Turquoises and Manganese Purples.
Also used to produce Craquelle effects.
To “Soften” high firing glazes by replacing feldspars.
A 7% addition plus 3% china clay improves glaze “fit” with undeglaze decorated once-fired ware.
Softening Point = 575C
Expansion = 0.97