The ryō was a gold currency unit in the shakkanhō system in pre-Meiji Japan. It was eventually replaced with a system based on the yen.
Keichō-period koban with value of one ryō
The yen is the official currency of Japan. It is the third-most traded currency in the foreign exchange market, after the United States dollar and the euro. It is also widely used as a third reserve currency after the US dollar and the euro.
One rin coin from 1873 (year 6 of Meiji)
50 sen coin from 1870 (year 3 of Meiji)
Early 1-yen coin, 26.96 grams of 90% fine silver, Japan, Meiji year 34 (1901)
20 yen coin from 1870 (year 3 of Meiji)