How it began
Rai are stone disks used as money on the Yap islands, now a state of the Federated States of Micronesia. It is not known how long they have been in use. The earliest European reports that may describe them come from Jesuits in the early 1700s. The stone is not found on Yap: Yapese crews sailed to Palau, about 400 kilometers away, and cut the disks from calcite deposits in caves there. Quarrying at one Palau site, Metuker ra Bisech, appears to have begun around 1700, after the Yapese obtained iron tools.
How it works
Disks were cut from the quarry wall as rough upright rounds and pierced with a central hole so a log or bamboo pole could be passed through for carrying. They were brought home by canoe or, for large pieces, on bamboo rafts. The Smithsonian explains that because the stones are so heavy, the Yapese did not move them when they changed hands on the island. People remembered who owned which stone, and the stones stayed where they stood in the villages. The history of each stone's exchanges set its value.
How it spread
Expeditions to Palau involved tens of young men sent by a village chief and could last years; men died at the quarries and at sea, and stones were often lost. In 1871 the Irish-American trader David Dean O'Keefe was shipwrecked near Yap. He later used his ship to bring stones from Palau for the Yapese in exchange for copra and sea cucumber. These newer stones were judged less valuable than older ones, and the Smithsonian says his supply introduced inflation. Stones could also be given between islands: a Palauan delegation was recorded carrying a rai to Yap as a diplomatic gift.
What lasted
The Smithsonian acquired a rai in 1962 for 200 US dollars with the help of Yapese anthropologist Francis Defngin. That stone had been quarried in Palau and taken to Yap in 1904. Cora Lee Gillilland's 1975 Smithsonian study, The Stone Money of Yap, remains a standard numismatic survey of the disks.
Where it stands today
Yap now uses the US dollar as its standard currency, and rai remain standing in villages across the islands. The Smithsonian's stone is displayed at the National Museum of Natural History in Washington, where it was first shown in 1962 at the opening of the Cultures of the Pacific exhibition.
