I agree with Vernelle – it
I agree with Vernelle – it sounds like small bubbles trapped between layers of glass.
You would think that the super smooth machine rolled surface on System 96 glass would eliminate bubbles but I think it actually can make it more difficult for the inevitable air between layers to escape. When I use Bullseye Tekta – which is machine rolled and has one textured side and one smooth side I make a point to never fuse smooth-to-smooth for this reason.
Did you have a bubble squeeze in your schedule?
Helios Kiln Glass Studio