100-yen coin (百円硬貨)
The 100-yen coin is a subsidiary coin issued by the Japanese government. It is called 'hyaku en koka' or 'hyaku en dama' in Japanese. The Japan Mint defines that the side on which the year is marked is the tail side for convenience sake, however, unlike coins from the Meiji period, the 100-yen coin legally has no head or tail.
The 100-yen cupronickel coin
This is the 100-yen coin that is currently issued. On the head side are the designs for 'Japan', '100 yen' (both in kanji) and Japanese cherries, and on the tail side is the number '100' and the year of manufacture. On the lateral side, there are 103 knurls. For the character for '100,' a design similar to the character for '50' on current 50-yen coin is used.
The 100-yen silver coin
In 1957, the 100-yen silver coin was issued with the design of a "Hoo" (a mythological sacred bird in Chinese lore, a phoenix) as the first silver coin minted after the war. The cost of manufacturing at that time was said to be 43 yen. In 1959, the design was changed to ears of rice while the weight and composition were unchanged. At the same time, the design of the 50-yen coin was also changed and both designs were sought from the public.
The content of silver in these two types of 100-yen silver coins is 0.600. As of 2008, the value of silver hovers around 50 yen per gram. Assuming it is 50 yen, the price of silver contained in a 100-yen silver coin is (50x4.8x0.6) 144 yen, which exceeds the face value. If the value of silver were to go even higher, there is a potential risk that the coin will become subject to illegal acts against the Act on Control of Damaging and Other Acts Related to Coins.
Also refer to Japanese silver coins.
Transition
1957: The 100-yen silver coin was issued.
1959: Design of The 100-yen silver coin was changed from hoo to ears of rice.
1967: Current 100-yen cupronickel coin was issued.