Card #428 · HistoryDex
Rai Stones
The puzzle
Where?Where was this currency used?
When?Around what period was this currency used?
Reveal the answer
The answer
- Place
- Yap Island (Micronesia)
- Date
- c. 1400 → 1931
In the app: the right region in Explorer mode, within 1200 km in Historian mode.
Pierced calcite discs, some as tall as a person, used as money on a Pacific island. Their value lies mainly in their history.

Rai Stones
Micronesia · c. 1400 → 1931
Large stone discs pierced through the centre, sometimes taller than a person, used to pay. Their value lies mainly in the risks taken to transport them.
On the island of Yap, in Micronesia, huge stone discs pierced through the centre, the rai, serve as money from about 1400 to 1931. Their value lies mainly in the sea voyages, sometimes deadly, to bring them back from the quarries of Palau, 400 kilometres away. A rai that changes owner does not necessarily move: the community remembers who owns it.
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