The island of Yap in Micronesia has a special monetary system. Although using simple shells for small transactions, significant amounts are sometimes paid with pieces of stone, some weighing tons.
The value of the stones was kept high due to the difficulty and hazards involved in obtaining them. To carry the stones, Yapese adventurers had to sail to distant islands and deal with local inhabitants who were sometimes hostile.
The scarcity of the disks, and the effort and peril required to get them, made them valuable to the Yapese. However, in 1874, an enterprising Irish sea captain named David O'Keefe hit upon the idea of employing the Yapese to import more "money" in the form of shiploads of large stones, from the island of Palau. O'Keefe then traded these stones with the Yapese for other commodities such as sea cucumbers and copra.
The 1954 movie ''His Majesty O'Keefe'' which cast Burt Lancaster as the captain was Hollywood's way of telling this historical tale. As no more disks are being produced or imported, this money supply is a fixed commodity. The islanders know who owns which piece but do not necessarily move them when ownership changes.
Today, stone money is still used, but the shells were replaced by dollars.
- Source 1: Collected via email
- Source 2: Web searches