People of Yap islands used to use large round stones usually carved of limestone as money. These stones known as “Rai” were quarried on Palau island and then transported to Yap islands. These stones have a doughnut shape with a hole in the middle.
Each stone had a history of its origin and of deals where it had participated. That’s why it made no sense to steal Rai: if the deal wasn’t officially registered in Yap’s history, the stone still belonged to its old owner. The owner had to proclaim that he no longer owned the stone and give it to a different person.
The size of stones varies to a great extent: the largest are 3.6 metres in diameter, 0.5 metres thick and weigh 4 tonnes. The smallest rai stones might have a diameter of 7–8 centimeters. The largest disk on Yap archipelago is located on Rumung island, neighboring to Yap island.
Another reason that locals historically praised the discs was due to the fact that their composition looked like quartz. This material was the most glittering in the vicinity. Gradually the stones became a legal payment currency and were even required to be used in some deals. In 1929 it was calculated that there were 13 281 “coins” on the island.
Usually it was a custom to place these stones next to the house showing off the owners’ wealth.
As with any currency, stone money attracted forgers. The most famous among them was David Dean O’Keefe, American sailor of Irish origin. He understood the value of the unusual money but didn’t feel like quarrying and transporting them. David simply took on producing them with a help of modern instruments and materials imported from Hongkong. This practice lead to inflation and devaluated stone money.
Unfortunately, modern banknotes and credit cards have long ago replaced Rai, however the stones still are an important cultural part and a symbol of both Yap and Micronesia. They are used in many important social transactions, such as marriage, inheritance, political deals, sign of alliance and they are also depicted on local license plates.