Emperor's 60th Year of Reign Commemorative 500-Yen Cupronickel Coin | Design, Specifications and Mintage

According to the Imperial Household Agency, Emperor Shōwa was born on 29 April 1901 (Meiji 34) and succeeded to the throne on 25 December 1926 (Taishō 15), becoming the 124th Emperor. From 25 December 1985 (Shōwa 60), he was in the 60th year of his reign.

The date of the commemorative ceremony was set out at a Cabinet meeting on 27 December 1985. As read out in the Diet, the statement at that meeting was that "a commemorative ceremony hosted by the Cabinet will be held on Tuesday 29 April next year (the Emperor's Birthday)". The Imperial Household Agency records that ceremonies marking the 50th and 60th years of his reign were held in Shōwa 51 and Shōwa 61.

The issue of commemorative coins was one of the celebratory projects for the 60th year, and the Ministry of Finance was in charge of it. The same list of projects also included commemorative postage stamps from the Ministry of Posts and Telecommunications and commemorative railway tickets and Orange Cards from the Ministry of Transport.

The obverse shows the Shishinden hall. The Ministry of Finance's List of Commemorative Coins describes it as "the building where His Majesty's enthronement ceremony was held". According to the Deputy Grand Steward of the Imperial Household Agency in the Diet, the Shishinden enthronement-day ceremony was held in the Shishinden of the Kyoto Imperial Palace on 10 November 1928 (Shōwa 3); about 2,200 people attended, and the Emperor ascended the Takamikura throne. The reverse shows the chrysanthemum crest.

How the design was decided was also explained in the Diet. According to the Director-General of the Ministry of Finance's Financial Bureau, the Mint prepared a number of proposals, including one with the Emperor's portrait. The Imperial Household Agency told the Ministry of Finance to treat the portrait with caution at its own judgment. The design was not put to public competition; the Mint worked on it with guidance from members of the advisory group, including Hirayama Ikuo, who collected and studied coins from around the world.

Under the Temporary Currency Act of the time, coins with a face value above 500 yen could not be issued. The government therefore submitted a bill covering only the 100,000-yen and 10,000-yen coins, following the precedent of the 1,000-yen silver coin for the Tokyo Olympic Games. This became the Act on the Issuance of 100,000-Yen and 10,000-Yen Temporary Subsidiary Coins to Commemorate the 60th Year of His Majesty the Emperor's Reign (Act No. 38 of 1986), promulgated on 28 April 1986. The 500-yen cupronickel coin was not covered by this Act; it was issued as one of the coins of 500 yen or less that the Temporary Currency Act already allowed.

How the face values and numbers were decided was also explained in the Diet. At an advisory meeting held on 9 December 1985, many members said that a gold coin should be a fine one of about 100,000 yen, and that silver and cupronickel commemorative coins should be issued alongside it. The total number was 70,000,000, the same as for the 50th year of the reign. The Director-General said that the figure of 70,000,000 for commemorative coins had started from a calculation of roughly two coins per household, and that, alongside 10,000,000 gold coins, the 10,000,000 silver coins and 50,000,000 cupronickel coins were worked back from minting capacity.

According to the Bank of Japan, the ordinary 500-yen cupronickel coin was first issued in 1982 (Shōwa 57); it is 26.5 mm in diameter, weighs 7.2 g, and has lettering on the edge. This commemorative 500-yen coin is the same cupronickel of copper 750 and nickel 250, but at 30.0 mm and 13.0 g it was made larger and heavier than the ordinary 500-yen coin.

In the Ministry of Finance's list, 500-yen commemorative coins began in Shōwa 60 with the International Exposition and the 100th Anniversary of the Cabinet System, and this 60th-year coin is the third.

The 100,000-yen gold coin for the same occasion was exchanged by lottery to give everyone an equal chance. Coins dated Shōwa 61 and Shōwa 62 together came to 11,000,000.

On 29 January 1990 (Heisei 2), the counterfeiting of this gold coin came to light when a financial institution in Tokyo reported it to the Metropolitan Police. According to the National Police Agency's answers, three coin dealers in Japan had imported about 105,000 pieces between around March 1988 (Shōwa 63) and around January 1990, and the goods had been taken out of Switzerland. The counterfeits were described as having linear scratches on the characters for "60th year of reign" and "Shōwa 61", shallower relief and a duller surface.

Following this case, the weight of the 1990 Emperor's Accession 100,000-yen gold coin was increased from the planned 20 grams to 30 grams.