Hi Doug:

Sorry to hear about the accident. What do one of those blanks run now days?

Kilns large enough to remelt a 24" fall into the studio category of kilns and that poses a problem. There are fewer people that have that size and most of those kilns are cone 8. Since your blank is broken a remelt is required instead of just fusing. This will require a cone 10 kiln. There is also a reasonable argument that it should be a gas fired kiln if a remelt is to be involved. This has to do with oxidization of components that can change the physical characteristics of the glass. Otherwise a flux maybe required. As Bob said, it may pay to take a local community college class that may have the required kiln. Unfortunately at our own local college the giant kiln does not go hot enough and they don't have the fine annealing formulae. A melt needs constant attention in the first 24 hrs so if it cannot be attended to, the kiln needs to have a computer control. Hope this information helps you narrow the leads down. Let us know how it works out.

Good Luck -Rick