One-yen aluminium coin

Issued in June of the thirtieth year of Shōwa. Pure aluminium, 20 millimetres across, weight 1 gram. The design was the first after the war to be sought from the public, and the young tree on the face by Nakamura Masami and the '1' on the back by Takashima Tonio were chosen. Out of more than 2,500 entries, lines drawn by citizens whose names were not known became, just as they were, the design of the nation's money.