There are two main species of cowrie shell found throughout West Central Africa, Cypraea moneta and Cypraea annulus. Both species are found in the Indian Ocean, the first from the Maldive Islands and the second from the East African coast. Both species of cowrie shell were used as currency throughout West Central Africa where this form of money was known locally as nzimbu. Cowrie shells were likely introduced to West Central Africa by Western European nations like Portugal which, in the 15th century, established new trade routes that connected West Central Africa to the East.
The rarity of these shells in West Central Africa was what allowed for their value. Today, cowries are no longer used as currency, but their historical and cultural significance continues to lend them significance. As such, they are still considered a symbol of wealth and luxury. In some parts of Africa these shells are used in divination rituals. Their value, therefore, lies not only in their monetary worth, but in their cultural and spiritual significance.