Some sources attribute their introduction to the ancient Phoenicians who traded along the west coast of Africa or even early Carthaginian explorers and traders. The Egyptians have also been suggested as they used penannular money. One suggestion is that Nigerian fishermen brought them up in their nets from the shipwrecks of European wrecks or made them from the copper 'pins' used in wooden sailing ships wrecked in the Bight of Benin. One theory is that if indigenous, they copied a splayed-end Raffia cloth bracelet worn by women, another that the Yoruba "mondua" with its bulbous ends inspired the manilla shape.