The slaves would harvest natural clay from the land or if they were lucky maybe get their hands on some scrap clay from some type of factory setting, which was usually higher in quality. They would create works of arts which resembled "ugly faces" but were and still are considered beautiful to this day. The pots were cooked on an open wood fire with ugliness being the focal point for one critical reason. The fact that the uglier the face, the more effective it was at driving away evil spirits while simultaneously functioning as their grave marker. Moreover, it was believed that the ugly jug had to sit for a full year at least to guarantee the spirit a safe passage to the afterlife. If something were to happen to the jug, such as break, the spirit would then enter into a struggle with the devil. This was a tarrying prospect to the African slaves and thusly, the popularity of the face jugs spread.