The Stone Money Nobody Could Move

Rai stones are limestone discs, drilled with a hole in the middle, that the people of Yap quarried four hundred miles away on Palau and ferried home on outrigger canoes. The largest surviving stone is twelve feet across and weighs about four tons. Moving one was so risky that on at least one famous occasion a rai sank in a storm on the trip back to Yap.

The stone stayed at the bottom of the Pacific. The village that had quarried it kept spending it anyway. Ownership transferred by oral agreement: everyone knew whose stone it was, and that was enough. The disc itself never had to surface for the wealth it represented to change hands.

Milton Friedman, writing in 1991, found the system less strange than it first looks. The Federal Reserve Bank of New York settles gold transfers between countries by walking bars from one cage in its basement vault to another — the metal never leaves the building, but the ledger entry behind it changes hands. A rai at the bottom of the sea is the same idea with worse weather. What money is, in both cases, is a shared belief about who has a claim on a thing.

The system survived contact with German colonial authorities, who in 1903 tried to force Yapese villagers to repair footpaths by claiming a portion of their stones — marking selected rai with a black cross to signal the colonial government now owned them. Once the work was done, the crosses came off. The stones, again, did not move.