The treasure was found during excavations carried out before the construction of the facility. Only 334 coins have been examined so far; the oldest of these comes from China and dates back to 175. with of our era and the newest – in 1265 of our era.

Detail

The coins were found in 1,060 bundles containing approximately 100 coins each. The oldest coin has the Chinese text “Banlian” engraved on it. “Banliang” coins were common in China about 2,200 years ago. The inscription translates as “half an ounce”.

Many coin hoards have been found all over Japan, and some were even larger than this one. Mostly caches date back to the 13th-16th century. They contain coins from centuries, but from different periods of history. The fact is that the Japanese began to produce their own metal currency only at the end of the seventh century, creating coins with a square hole in the middle according to the Chinese model.

The hole was used to allow people to stack large numbers of coins; usually 100 coins per string.
says Ethan Segal, a history professor at Michigan State University who was not involved in the dig.

As you can see in the pictures, the coins found have holes / Photo by Maebashi City Government/Eiichi Tsunozu

Bundles of coins / Photo by Maebashi City Government/Eiichi Tsunozu

As the scientist explains, the Japanese minted their own coins until the mid-10th century, but then stopped doing so due to changes in the economy and insufficient supply of copper ore. Chinese coins were sometimes used instead. Segal also says he wouldn’t be surprised if most of these coins turned out to be from the Northern Song Dynasty (960-1127 AD). The Northern Song produced a large number of coins, but after the takeover by a nomadic group called the Zhurzhenei in the early 12th century, their coins lost value and people preferred to use them to purchase goods abroad.

Coins found on the ground / Photo by Maebashi City Government/Eiichi Tsunozu

Who hid them and when

Such a hiding place can serve as a bank or fulfill a certain symbolic meaning – for example, a religious meaning as a sacrifice to the gods. They can also be hidden to protect them during war because that much money is too heavy and you cannot take it with you.

Scientists will be able to determine when the treasure was buried and even who buried it. The fact that the last coin examined so far dates back to 1265 suggests that the treasure may have been buried shortly thereafter. This was the Kamakura period, when Japan’s warriors played an increasingly important role in establishing the shogunate (a system in which the emperor effectively allowed a shogun, or military governor, to rule), headquartered in Kamakura, near modern-day Tokyo. According to archaeologists, the location and period of the treasure “suggest that those who buried it were warriors from this region.”

However, the dating of the hoard may be premature, as only a small number of coins have been examined and may contain coins dated after 1265.

Coins found on the ground / Photo by Maebashi City Government/Eiichi Tsunozu