This paintable clay sticks to most materials including gourds, wood, glass, metal and plastic. A favorite of gourd artists because of it's many uses. A white, non-toxic modeling compound that completely hardens with very little shrinkage after air drying for just 24 - 48 hours, so there's no firing required. Once opened, put your remaining clay with a wet paper towel in a seal-tight bag and place in the refrigerator until you need it again.