Ancestral altars dedicated to past iyobas, like those of past obas, are furnished with cast brass commemorative heads. The heads of queen mothers are distinguished from those of kings by the forward-pointing peaks of their coral-beaded crowns. Commemorative heads of iyobas hold to the same stylistic chronology as those of obas. Earlier heads were cast with thinner walls and display tight beaded collars that fit snugly beneath the chin. Later versions have thicker walls, exhibit enlarged cylindrical collars that cover the face up to the lower lip, and are designed with a circular opening behind the peak of the crown to hold a carved ivory tusk. With its high and narrow collar, extensive hair ornament, and pierced crown, this commemorative head of an iyoba dates from the eighteenth or nineteenth century.