The Micronesian island of Yap has a famously unusual currency: hundreds of giant discs of rocks scattered all over the island, many of them too heavy to move.

Arriving on the tiny Micronesian island of Yap will fill even the most jaded traveller with a sense of awe. The single daily flight comes in over dense forests, taro swamp, shallow lagoons and a web of mangroves, all surrounded by fringing reef. But the real wonderment doesn’t come from the idyllic scenery, nor from the greeting by a Yapese girl in a traditional hibiscus skirt. It’s when you first come face-to-face with a piece of giant stone money.

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Hundreds of these extraordinary, human-sized discs of rock are scattered all over the island; some outside the island’s few hotels, others in rows close to the beach or deep in the forests. Each village even has a stone money bank where pieces that are too heavy to move are displayed on the malal (dancing grounds).

“My family owns five stone money of a good size,” said Falmed (Yapese just use one name), a taxi driver I flagged down to take me to Mangyol stone money bank in Yap’s eastern province of Gagil.

Five, it turns out, is a good haul, since many islanders don’t own any stones.

The unique stone currency has been in use here for several centuries, although no-one is quite certain when the concept began. What is known is that each one is different, and they are as heavy with meaning as they are in volume of limestone, carved and voyaged by the Yapese all the way from Palau, an island nation 400km to the south-west. The very first pieces were used as gifts and shaped like a whale – thus named ‘rai’ stones – but they’ve evolved to become currency, including holes carved through the centre to make them more transportable across the oceans.

“My forefather Falmed, he is the one who started to go to Palau first by canoe, and make this connection between Palau and Yap. So I carry his name,” Falmed told me as we hurtled along dirt roads past the sleepy capital of Colonia. Despite his sun-worn T-shirt and rickety car, his lineage is surprisingly significant. His distant forefather Falmed was a high chief powerful enough to commission a boat to Palau where he met with locals and gained access to a quarry site.

“He came back and called a meeting where he told the village to gather tuba, the local alcohol, to trade,” Falmed said. Within a month, he was back in Palau to start carving the stone as money.

The issue was that Yap had no durable rock or precious metals with which to make coins. Instead, experienced Yapese sailors, commissioned mostly by wealthy high chiefs, would sail to Palau on bamboo rafts, and eventually, schooners, to load up with limestone from their quarries. Initially small, as techniques and tools improved, the coins became even larger than the people who would painstakingly carve them. When metal tools were introduced by European traders in the late 19th Century, quarrying was made easier, and reports from the 1880s claimed 400 Yapese men could be found working in just one quarry in Koror, Palau – a significant proportion of the population, which would have then been about 7,000 in total.

On their return from Palau, the sailors would give the carved stone money to the high chiefs who would gather from different villages to welcome back the sailors and the stones. The chiefs would keep the larger ones and two fifths of the smaller ones. They would also give names to some stones, usually choosing their own name or that of relatives, and confirm the stones as legitimate by giving a value based on an even older currency system: yar (pearl shell money). The stones could then enter circulation and be bought by anyone.

“If the chief says OK, 50 shell money for each stone money, if I have that I will make the trade and own one,” explained Edmund Pasan, a canoe builder from the northern province of Maap.

Today, shell money has been replaced by the almighty US dollar for day-to-day transactions like grocery shopping. But for more conceptual exchanges, like rights or customs, stones remain a vital currency for Yap’s 11,000 residents.

Falmed’s family has only used its money twice, and one was as an apology. “We used it for one of my brothers who made trouble for another family,” Falmed revealed remorsefully. His brother’s marriage had failed. “One of the chiefs, his daughter got one piece of stone money as an apology, and they accepted it. When it comes to high ranks, you have to use stone money.”

When it comes to high ranks, you have to use stone money

The value of stone money has always been fluid, challenging the Western concept that currency value is pre-determined and fixed. The coins are valued by their size – they range from 7cm to 3.6m in diameter – as well as their ornateness and even for the sheer difficulty in obtaining the rock. How much a coin is worth also depends on who you give it to, and what for.

In addition, Yapese factor oral history into each stone’s value, as there’s no written record of what belongs to who. Families rarely move from their villages, and the tribal elders from the around 150 villages pass down information of each piece, meaning they act as a reminder of the past and help to reinforce relationships and transactions that date back to times of warriors and clans. In some cases, the stones have engravings marking battles from more than 200 years ago.

Falmed and I finally arrived at the Mangyol stone money bank after a 40-minute drive from Colonia. From large to small, the few dozen stones were lined up in front of a p'ebay, an open structure in the village centre where the community comes together to do their trade, celebrations and sometimes their schooling too.

Falmed explained that the rai are specifically placed, each encoded with secret connections, village relationships, and stories of marriage, conflicts and deep apologies that have seen the stones change hands over centuries. It’s those stories that only the local villagers know that truly determine which is most valuable. There’s no need to make more rai since the island essentially has a permanent number in circulation, and few are ever moved. Even broken ones retain their oral history that give them more value than a new piece. New pieces are occasionally made, though, simply to ensure the skills of past generations are not forgotten.

It’s those stories that only the local villagers know that truly determine which is most valuable

But if the stones are so valuable and so public, I wondered, what’s to stop someone making their own, or simply stealing one?

“Most matters are common knowledge and secrets among local people are rare; thus theft of rai is relatively unknown,” writes Cora Lee C Gilliland of the Smithsonian Institution in her paper The Stone Money of Yap.

Not that some haven’t attempted it. “They tried to do that in Yap, and they laughed about it because they broke,” Pasan later told me with a chuckle. “Then they did it with the stones in Guam, but they are not that strong and are more difficult to get at – it’s much easier to quarry in Palau.”

Yap’s neighbours, Guam, Palau and Chuuk, are all heavily affected by European and American colonisation, and all bear conspicuous scars of World War II. Guam remains a US territory with a significant military base on the island that has shaped its culture, while Chuuk Lagoon is home to around 60 sunken wrecks, a result of the devastating Operation Hailstone in 1944.

Yap, though, was largely bypassed by US bombing as the early 20th-Century Japanese occupation came to an end, and the rai stone’s sturdiness and longevity seem to represent the long-lasting authenticity of Yapese culture over the centuries.

“In Yapese culture, if something [important] is going on, and there is nothing else suitable to use, then you use stone money,” said Falmed, who has already ensured the next generation retains his wealth by passing one piece to his son at his first-birthday ceremony.

“When my girlfriend was pregnant, we [came here] from Hawaii,” he explained. “On a child’s first birthday, if a clan is of high rank and has some small stone money, they will cut a chicken and drain the blood on the boy’s head to recognise the moment. It’s a gift, and a lot of people came [to the ceremony].”

Falmed’s son is 12 now and lives in Hawaii. But the stone is in his family house in Yap. And even without written record, everyone already knows whose name is on it.

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