In 1870, gold coins were introduced of denomination such as 2, 5, 10, and 20 Yen. Afterward, in 1871, Gold 1 Yen was introduced. In 1897, the silver 1-yen coin was demonetized and the sizes of the gold coins were reduced by half, with 5-, 10- and 20-yen coins issued.
During Second World War, production of silver coins annulled in 1938 and which led to base metals coins of 1, 5, and 10 Sen. It is interesting to note that clay coins of denomination 5 and 10 Sen were produced in 1945, but not released for circulation.
The Japanese 20 gold yen of 1870 contains 33.33 grams of gold and weighs 0.9645 ounces. It was minted between 1870 and 1932. It composed 90 % of gold and 10 % copper. During their lifespan was the highest denomination of the coin that circulated in the country.
Many of these coins were then melted or destroyed as a result of the wars between 1931 and 1945. Now they are collected by numismatists or used for research purposes.
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