"he owed every neighbor some money, from a few cowries to quite substantial amounts"
Cowrie Shells
Creative Commons Attribution Share AlikeCowrie Shells - Credit: Sodabottle

Cowries have been used as currency in various cultures. In fact the classical Chinese character for money is said to derive from a cowrie shell.  The shells come from marine snails, and can reach up to four inches in length.

Olive-sized white and yellow cowries were used by the Igbo. They symbolize wealth, importance, and fertility.