Hi, I am hoping someone can help me understand how to make sure glazes I make from recipes are non-toxic. I won't be using any lead, but obviously other oxides are toxic, and I read warnings about them but no advice on how to make sure the finished piece is food safe. I'm getting back into pottery after several years idle (no kiln access), and all my prior experience was in classroom situations where the instructors prepared the glazes and suggested which to use.
I'm also hoping to create dinnerware that will withstand normal use without knives marking the finish. I'll be firing in a Paragon Touch n Go, trying to keep it to cone 6 to keep the kiln lasting a while. I've read that there are tests, but what are they? I have lots of questions, actually.
One more question - I remember that cobalt oxide needed to have an overglaze to turn blue - is there any specific clear glaze, or would any one do it?
Thanks so much. I've been reading like crazy, but I can't find all my notebooks, and it's maddening to remember bits and pieces and not have my instructor there to ask!