Special products such as yakogai (turban shell, lunica marmorata) and bishop wood (Bischofia javanica), which were used as materials for handicrafts, were brought from Minami-jima Island in return for iron wares.
南島からは工芸品の材料となる夜光貝や赤木といった特産物がもたらされ、また南島へは鉄器がもたらされた。