The large number of commemorative heads from this period are highly formalised. Their faces are largely identical, while the royal insignia are more elaborate and their shapes vary, with the coral bead cap being a common feature. Various motifs on a plinth around the base refer to the spiritual power of the king. At the same time, the heads became larger and their walls considerably thicker. On the altars of the 18th and 19th centuries, the memorial heads also serve as a base for large elephant teeth, which are carved with motifs that were depicted on the relief panels in Benin's early period, in the 16th and 17th centuries.