Every currency in history is, at its core, a shared hallucination — a collective agreement that this thing, whatever it is, counts as value. Gold works because everyone says so. Dollars work because everyone says so. The only difference between "real" money and fake money is the number of people who've agreed to pretend. Which, when you zoom out, explains everything below.
1. The Rai stones of Yap: money too big to spend
On the island of Yap in Micronesia, the traditional currency was limestone discs — some as large as 3.6 metres across and weighing several tonnes. Moving them wasn't really an option, so ownership transferred by public spoken agreement instead. Everyone in the community simply acknowledged who the stone now belonged to, and that was that. The stone didn't budge. The ledger did.
The most remarkable case: one Rai stone was lost to the sea floor during transport. It never surfaced again, and it didn't need to. The community agreed it existed, agreed who owned it, and the stone continued to function as valid currency from the bottom of the ocean. Economists have been citing this story ever since as proof that money is, and always was, a social fiction — just usually a drier one.
2. Salt: the original salary
Before refrigeration, salt was the only practical way to preserve food. That made it extraordinarily valuable — and in the ancient world, extraordinarily useful as currency. Roman soldiers were reportedly paid partly in salt, or given an allowance specifically to buy it. The Latin word for that allowance was salarium. The word "salary" has been following you around ever since. Whether the phrase "worth his salt" dates to the same root is debated by etymologists, but the underlying point stands: at various points in history, salt was worth fighting over, trading for, and counting out in careful lumps.
3. Cigarettes: the most-documented alternative economy in history
In WWII prisoner-of-war camps, Red Cross parcels arrived containing cigarettes, chocolate, and other goods. Within weeks, a fully functional market economy emerged, with cigarettes as the reserve currency. Prices were quoted in cigarettes. Exchange rates existed between compounds. Non-smokers held cigarettes purely as a store of value and traded them for other goods — an early instance of people holding an asset they had no intention of using.
We know this in unusual detail because economist R.A. Radford was one of the prisoners and wrote it all up in a 1945 paper for the journal Economica. It covers inflation (when Red Cross deliveries arrived, prices rose sharply), deflation (when they stopped), price-fixing attempts, and arbitrage between different camps. It remains assigned reading in economics courses to this day.
When supply surged — a big Red Cross shipment, a new batch of prisoners arriving with full parcels — cigarette prices rose and the purchasing power of each cigarette fell. When supplies dried up, deflation. The camp had, without intending to, replicated the entire monetary cycle. All it was missing was a central bank arguing about it on television.
4. Squirrel pelts: medieval Russia's small-change solution
In medieval Russia, fur was currency — and not just metaphorically. Squirrel pelts were used in everyday transactions, with specific pelts (muzzle, claws, ears) serving as smaller denominations when a whole pelt was too much. The system was practical enough: fur was durable, portable, divisible, and in steady demand. It only stopped making sense when coins became widely available and "I'll pay you in squirrel" started to sound like what it was.
5. Cowrie shells and the "Made Beaver": global small-change
Cowrie shells — small, smooth, durable, and satisfyingly uniform — served as currency across enormous stretches of Africa, South Asia, and East Asia for thousands of years. Their range makes the dollar look provincial. In North America, the Hudson's Bay Company ran its fur trade on the "Made Beaver" unit: the value of one prime adult male beaver pelt, against which everything else was priced. A blanket cost so many Made Beaver. A gun cost more. The company printed tokens denominated in fractions of a beaver. This is not a metaphor.
6. Cocoa beans: Aztec money with a counterfeiting problem
The Aztecs used cocoa beans as currency — which put them in the unusual position of having a monetary system you could also drink. Cocoa beans were traded, hoarded, and used to pay tribute to the state. They were valuable enough that counterfeiters existed: people who hollowed out beans, filled them with mud or sand, and passed them off as the real thing. The Aztecs had, in other words, invented both money and financial fraud from the same starting ingredient.
7. Tide detergent: "liquid gold" in the 2010s black market
In the early 2010s, US retailers began noticing an unusual pattern: bottles of Tide laundry detergent were being stolen at scale, consistently, and then turning up at corner stores and flea markets at a discount. Investigators eventually pieced together that Tide had become an informal black-market currency — recognisable, high-value, and with a stable street price of roughly half the retail cost. Drug dealers were accepting it in lieu of cash. Shops were fencing it. Loss-prevention teams were installing Tide-specific security measures. The brand had, entirely without planning to, become legal tender in an entirely illegal economy.
8. Parmesan cheese: the currency sitting in bank vaults right now
This one is still happening. Some Italian banks — most famously Credito Emiliano, operating in the Parmigiano-Reggiano heartland of Emilia-Romagna — accept wheels of Parmigiano-Reggiano as loan collateral. Cheesemakers deposit their wheels, borrow against them, and reclaim the cheese once the loan is repaid. The banks store the wheels in climate-controlled vaults and periodically inspect them for quality. The cheese ages. Its value increases. In an era of zero interest rates, Parmesan was outperforming some bonds. There are currently hundreds of thousands of wheels sitting in Italian bank vaults, quietly maturing into collateral.
Sources & further reading
- R.A. Radford (1945), “The Economic Organisation of a P.O.W. Camp,” Economica
- NPR Planet Money — “The Island Of Stone Money”
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