Report Bubbles In Black Stoneware in Studio Operations and Making Work Posted March 5 32 minutes ago, Hulk said: Per my limited experience, a hold at peak - adding heat work - may cause more fizzing. More heat work might clear things up for you, hmm. Are you firing same glazes, applied about same thickness, to other clays in same firing? Seeing same bubbling? In other words, any evidence that the problem is the clay vs. the glaze. Looks like very small bubbles, which mostly heal over, but leave an orange peel look - excepting for the four (or so) larger holes, which may be a dry spot (where the glaze didn't wet the clay fully going on), or a larger chunk of something in the clay off gassing, or? I found dropping and holding to help. No doubt you've already found links to Tony Hansen's articles, e.g. Drop-and-Soak Firing (digitalfire.com) and Glaze Bubbles (digitalfire.com); keep on it! Keep good notes on each case... I was just answering you on my post! Yep! I found that schedule and was surprised! is it a 27hour firing??