She was searching for a a matte, mottled white, rustic. For functional surfaces. And it contained this frit. The source from which she got it did not mention the barium content. Barium is certainly not a requirement to achieve a matte surface at cone 6, there of lots of ways to do it. And there are multiple matte mechanisms that can be exploited.
Trafficking in Glaze Recipes
The trade is glaze recipes has spawned generations of potters going up blind alleys trying recipes that don't work and living with ones that are much more trouble than they are worth. It is time to leave this behind and take control.
|Materials||Pemco Frit P-626|
|Hazards||BARIUM and COMPOUNDS / Toxicology|