1 yen coin

One yen

Japan
Value	1 Japanese yen
Mass	1 g
Diameter	20 mm
Thickness	1.5 mm
Edge	Smooth
Composition	100% Al
Years of minting	1955–present
Obverse
Design	young tree
Design date	1955
Reverse
Design	"1" in a circle with year of issue in kanji
Design date	1955

The 1 yen coin (一円硬貨, Ichi-en kōka) is the smallest denomination of the Japanese yen currency. The first Japanese one yen coin was minted in 1870. The current design was first minted in 1955.

Current design

The front of the current aluminium one yen coin has the figure "1" in a circle with the year of issue in kanji below, and the reverse side has a young tree, intended to symbolize the healthy growth of Japan.

History

Early one yen coin (1.5 g of pure gold), obverse and reverse.

The first Japanese one yen coin was minted in 1870. Its obverse featured a dragon with a circular inscription around. The reverse had a radiant sun surrounded by a wreath, with chrysanthemum emblem (a symbol of the Japanese Imperial Family) flanked by floral patterns above. Large silver one yen coins were issued between 1870 and 1914, supplemented by small gold one yen coins issued between 1871 and 1880 (plus a special collector's issue from 1892). One yen silver coins minted after Japan adopted the gold standard (gold based currency) in 1897 were not issued for domestic use, but for use in Japanese Taiwan and foreign trade.

A brass one yen coin was minted during 1948–50.

The current design was introduced in 1954, when the first aluminium one yen coin was minted.

Non-monetary use

One Yen aluminium coin floating on the surface of water.

Since all 1 yen coins weigh 1 gram, they are sometimes used as weights. If placed carefully on the surface of still water, 1 yen coins will not break surface tension and thus can float.