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Hello lovely ceramics people! I've been having some bloat issues with one particular clay body. It's a buff cone 5/6. It's made by the ceramics store I use here in southern cal. Here's the scoop: When fired previously up to cone 5, there was zero bloat but I wasn't too pleased with my glaze results (Amaco's potter's choice - not in attached photo) so I fired up to cone 6, and first had the bloat. I called my clay shop and spoke to their clay-kiln guy (lovely and helpful) and he gave me his custom bisque program that he said would help with specifically with inorganic burnouts (he said something about iron?) that can happen with darker clays. Again, this is a buff, not something as dark as Black Mt. but he said this was the issue. Then I fired the next batch using the nifty bisque program to cone 6 and soaked for 10 minutes. The only modification I made was to do 8 hours in the candling phase instead of 12 as written, because I know my pieces are bone dry before I load my kiln. I was very hopeful for this next batch until... bloat again! We spoke today and he still believes the iron is the issue, but I'm unsure of what to do next. Do you think this clay isn't stable at cone 6? I know there isn't technically a huge difference in temp between cone 5 and 6 but I'm tempted to take some old bisque pieces that I have stored away and test them at cone 5. That brings us back to the issue of glaze maturation and so I'd like to let the pieces soak at cone 5 -- how long do you think is adequate? Could cone 5 and a long soak be the solution? I adore throwing this clay body, and I really feel like my throwing skills have improved due in part to the nature of this clay, so I'm hoping that I can figure this out and keep using it... plus I have at least 200 lbs of it sitting on a shelf in my garage that I'd hate to not use. I've attached one of my bloated pieces and the bisque program I used during this process. Please excuse my pencil scribble on the firing program... I was trying to figure out total firing time so I could drop the lid at the appropriate time. **my matte white glaze also made by my local store appears underfired? over fired? So many issues for this newbie. If you're still reading this... thank you! I truly appreciate the wisdom of this group! cheers, alli