Currency: Rai in Yap, Micronesia

Limestone disks, sailing to distant islands, Burt Lancaster, traditional transactions like marriage and reparation

Yap, an island on the western Pacific Ocean and part of the Federated States of Micronesia, might be easy to miss on a map. The islanders’ currency, however, is not: Yap is home to the rai, one of the most unique forms of currency in the world. Mined in nearby Palau, the Yapese quarried large chunks of limestone, and sometimes calcite, shaping them into huge, circular stone disks with a hole in the center. Scientists say the currency possibly dates back to 500 AD.

As a foreign mineral, limestone was very valuable to the Yapese at the time. The stones were consistently high-value because of the difficulty and hazards involved in obtaining them. To quarry the stones, Yapese adventurers had to sail to distant islands and deal with local inhabitants who were sometimes hostile. Once mined, the disks were transported back to Yap on rafts towed behind canoe-like sailboats. The scarcity of the disks, and the effort and peril required to get them, made them valuable to the Yapese.

The size of the stones varies, the largest being 12 feet in diameter and one-and-a-half feet in thickness, and weighing four tons. Smaller rai stones may only be a few centimeters in diameter, similar to coins.

The most fascinating part is how a stone’s value is determined. Size and craftsmanship are large factors, but more important is the stone’s history. If a great number of people perished – or none at all were harmed – in the retrieval of the stone, the rai stone’s value increases.

In 1871, Irish-American David Dean O’Keefe was shipwrecked near Yap and assisted by the native islanders. O’Keefe helped the natives, in turn, by gifting them with iron tools, not realizing the inflation he would cause in rai stone retrieval. As a result, rai acquired with O’Keefe’s help were considered less valuable than more historic stones. In 1954, a movie starring Burt Lancaster told O’Keefe’s story of shipwreck and adventure in Micronesia.

A still from His Majesty O’Keefe (1954)

Although today the U.S. dollar is the currency used for everyday transactions in Yap, the stone disks are still used for more traditional or ceremonial transactions. Their size and weight – the largest ones require 20 adult men to be carried – make them extremely difficult to be moved. No more disks are made on the island, but residents know who owns which stone piece and do not necessarily move them when ownership changes. The rai stones may change ownership during marriages, transfers of land title, or as compensation for damages suffered by an aggrieved party.