So what is squashed glass? This is a fused glass/kiln forming technique that I’ve been having a go at. As described it is glass put in the kiln to fuse but you have to weigh it down with a second shelf to ‘squash’ it as it fuses.
Glass is viscous at high temperature and up to a certain heat it conforms to the glass fusers mantra “the 6 mm rule”. This basically means that however many layers of glass you put on top of each other the finished fused piece will always end up 6 mm thick, unless you dam it, but that’s another technique!
Squashed glass is multiple layers of glass weighed down with another kiln shelf on top (and any other bits of kiln furniture you might have to hand) so that the pressure of all that weight will go down on the piece and the glass will flow and merge together. The finished glass piece is nice and level and will have a smooth texture from the kiln shelf.
After that you can cut up your sheet of squashed glass and cold work the edges to smooth them out and slump in a mould to get the shape you want for your finished pieces.