Generally speaking, pottery that is referred to as being pit fired, is not glazed, and has been fired in an open bonfire or primitive pit kiln. Pottery fired to this low temperature is porous and not watertight. Terra Sigillata (a liquid … Read
Lunar Eclipse raku pottery jar by ~anubistj on deviantART -- 13 inches tall with a combination of 5 different glazes. Raku fired pottery is a Japanese style of firing. Made from white porcelain-like clay
A popular crystal glaze based on zinc and lithium. Spray the glaze thinner near the bottom of the pot. with to one hour at the top temperature. Does not need a slow cooling. Also try with stannic oxide.