The cowrie shell is at once currency, ornament and, in Yoruba religion and its diaspora, a divining and consecrating instrument, and it is this last use that gives it its sacred standing.
Divining with shells
In one widespread form of Yoruba divination a set of cowrie shells is cast, and the pattern of shells falling mouth up or mouth down is read according to a fixed system to deliver the response of the deities, so the shells become the medium through which the divine word is obtained, a more accessible counterpart to the more complex divination of the Ifa priesthood. The shells are also used to consecrate and adorn the sacred objects and the emblems of the orishas, and they figure in the regalia of the deities and their priests, so the cowrie is woven through the material life of the religion.
From money to the sacred
The cowrie was a real currency across wide regions of Africa and beyond, and its value and its associations with wealth carried over into its religious use, so that the shell that served as money became also an ornament of the gods and an instrument of their speech. Carried across the Atlantic with the Yoruba traditions, the cowrie kept its divinatory and consecrating roles in the religions of the diaspora, in Cuba and Brazil and beyond, where shell divination and the adornment of sacred objects with cowries continued. The single small shell thus gathers together the economic, the decorative and the sacred, and in the hands of a diviner it becomes the means by which the deities are asked and answer.