600
The experts studied 334 coins. They were dated from different periods of time. The oldest specimen turned out to be a ban liang – the 1st single currency of the Chinese Empire. It dates back to 175 BC.
The ban liang is a round coin with a diameter of 2.3 cm, with a rectangular hole in the center. The earliest coin was minted in 1256.
According to the researchers, in the Middle Ages, where the cache was found, there were houses of Japanese nobles. Apparently, one of them hid it during the Kamakura period (1185-1333), when there was a great deal of infighting.
