removing devit

[gemhuyck]

I have slumped a plate and when it was done it has devit. I read a post in the archives that said to use nail polish remover, but that was all it said. Does it really work?

[Morganica]

Nope, not hardly. Devit is short for devitrification, and it means the glass is starting to crystallize--it's literally becoming something besides glass and it will spread/deepen with every subsequent firing. You remove it by sandblasting or grinding off the affected areas, and fire polishing. Or by heating it up enough to turn it back into glass--usually to more than 2000 degrees, which will obviously give you a puddle instead of a plate

Or you can cover it up with more glass, fire again, and mostly conceal it.