Frogskin glaze was particular to the eastern Piedmont region of North Carolina, dating back to around 1875. It is made by glazing a piece of pottery with Albany slip clay and firing it in a salt kiln. The sodium reacts with the high iron content of the slip clay to produce a mustard green color. Earliest examples have been on ware by J.D.Craven (1827-1895), Moore County (NC). The term "frogskin" is thought to have been coined by Jugtown Pottery owner Jasques Busbee sometime in the 1920's. It was part of the Jugtown glaze repertoire and, later, that of Ben Owen's Old Plank Road Pottery.