The modification and expansion of local earthenware on the East African coast in the Fourteenth century showed signs of the developing economy and possibly new foreign integration. A major distinction used in dating local pieces of pottery was the thickness. Before the 15th century, vessels (bowls) were 3 millimeters thick; By the end of the 14th century, the thin vessels were extinct, and potters began making the vessels 6 millimeters thick. Examples of both were found underneath the dated tomb, suggesting that it was during that time (before 1399) that this technical change was taking place. The most commonly found form of local earthenware at Gedi was round bottomed bowls with incised pattern at the rim.
Incised lines on local pottery were another form of protective decoration used against evil spirits. These decorations were especially significant in the preparation of food. Women were usually the ones to prepare and serve food. Due to the abysmal division between men and women, decorated bowls and pots were used to cook food. These bowls and pots were handled by women, who were far less pure than men. To protect the men who were eating the food, women were to only use these incised pieces.
Food, in the Swahili social and ritual context, was used as a protective mechanism against sickness and bad luck brought by evil spirits; similar to the way imported porcelain and beads are used as protective decoration against malevolent spirits. Therefore, the vessels in which food was prepared was very important. An example of a decorated vessel found at Gedi is jungu la mofa (4), one of the largest Swahili earthenwares documented. Firstly, these were used as storage jars and were buried during a special sacrifice called sadaka. The sacrifice called upon kind spirits to guard the food that was being stored. Secondly, these pots were often used as ovens and set into the ground of the houses. Women would often use these pots as storage jars when they were not being used to cook food.
Non-decorated pots were used in preparation of food that was not directly consumed by men. An example of this is a lid or kia. Kirkman found many of these lids at Gedi. Most of them were charcoal in color on the tops. Kirkman predicted that these were carbonized due to being used in infusing coconut with other spices. These infusions were then added to the main course, which would be cooked in a larger, decorated pot (such as the jungu la mofa). Since men were not eating these infusions directly from undecorated earthenware and they were mixed with large amount of other foods prepared in heavily decorated pots, the food was considered to be protected and safe for consumption.