Okay, probably another stupid question, but here goes. I have been
going through Clavell's glaze book and he keeps using Ultrox. After
looking in Hamer's book (didn't find it) and finally Hopper's (did find
it), it seems that Ultrox is definied as a "fritted zirconium
silicate". I have regular zirconium silicate. What is fritted ZS?
