Re: glass stuck to slumping molds
Just because they sell it doesn’t mean you should use it
If you decide to slump over ceramic molds, it is best to use a layer of 1/8″ thick fiber paper between the glass and the mold. This gives the glass a little “leeway” when it cools around the mold. There are various methods to try to get the glass off the mold, all of which might be used with varying degrees of success.
Here’s my experience with a ceramic floral mold from Delphi: http://jestersbaubles.blogspot.com/2010/04/we-broke-mold-on-this-one.html
Jester’s Baubles Fused Glass Designs