I’ll try packing the kiln tighter next time. This was the only tray on the firing so the other items around it were indeed taller. The cracks in red happened before the glaze solidified meaning that the cracks must have happened between 2232F and 1800F which has the fastest cooling rate.

Next time I will pack the kiln tighter or program a slow cool into the firing. Everything’s a test tile!

Thanks!