Did the happy dance just a bit too soon! I thought I was home free on the firing disaster for the first tile. It took awhile but there is a thin crack running in a slow arc. It started at the bottom and went half way in. I looked at it again today and the crack is across the full tile. It appears to only be on the underneath portion of glass (two pieces are sandwiched together). Let's hope it stays that way! It is fully and firmly mounted and grouted in place! Oy, the unpredictability of glass is both frustrating and captivating at the same time. Always a learning experience!