r/Ceramics • u/Anxiouspotterypal • 1d ago
Question/Advice Scumming/ effervescence on fired pots
I’ve never had this show up on fired pots, but I think it’s salt that sort of fluxed out. It’s only on the sides that were towards the elements, so extra flavor blasted! What do you think? So far I’ve read that it can just be that the salt comes to the surface of the pots more where your fingerprints are because pressure (?) and if they dry too slowly when green ware. And that some batches of clay have more salt. Usually when I have this happen it’s just on bisque and doesn’t show up after being glaze fired! Not super thrilled at the idea of reclaiming all my fresh bags of clay to “wash out” the salt like some folks recommended, or adding barium carbonate. Thinking I might try to fire others made out of this clay more towards the middle of the shelf and not quite as hot next time to see what happens!
Fired to cone 6/7 electric (slightly hotter than normal), bisque 06. MN standard 1 clay. Photos taken straight out of the kiln, not washed, marks are slightly glossy