This is a flashing slip used for the salt/soda kiln.
After wadding the gallery, I place the lid on the pot and the whole piece on a bat. I spray a medium thickness of flashing slip evenly over the entire exterior. I let it dry on the bat until it is ready to load into the kiln. The soda vapors or wood ash create a glaze when they land on a piece during the firings, adding nuances of color and texture.This recipe was shared Arylnn Nobel in the May/June 2021 issue of Pottery Making Illustrated.