“Phantom” WWII ceramic coins found in Kyoto warehouse

A large cache of ceramic coins made as currency in Japan in the last month of World War II has been discovered in a warehouse in Kyoto. Counting is still ongoing, but the estimated quantity is 500,000 coins in 15 wooden boxes both loose and in bags. They are known as maboroshi (meaning phantom or illusory) coins because they were destroyed en masse at the end of the war, so finding half a million of them is unprecedented.

In 1944, almost all of the metal Japan could get was dedicated to weapons, munitions and other military applications, leaving a fraction of the amount needed for the production new currency. The Japan Mint commissioned pottery manufacturers in the cities Kyoto, Seto and Arita to make prototypes of ceramic coins in ten, five and one-sen denominations (100 sen were worth one yen). The company in Kyoto was Shofu Kogyo Co., founded in 1906 as a manufacturer of export porcelain and industrial porcelain (high-voltage ceramic insulators, chemical porcelain) for the local market. In 1922, they embarked on a new endeavor: the research and manufacture of the first artificial ceramic teeth in Japan and by the end of the 1930s, were the leading producers of ceramic dental products in Japan.

In July 1945, less than a month before the end of the war, ceramic coins began to be mass-produced in Kyoto and Seto. About 15 million coins were made before production ended abruptly with the surrender of Imperial Japan on August 15th, 1945. The inventory of ceramic coinage was destroyed before entering circulation. That’s why they’re known as “phantom coins.” The entire sen denomination was discontinued after the war, and the last metal coins were taken out of circulation in 1953.

The Shofu Kogyo Company was dissolved in 1967 but its descendant, Shofu Global, is still going strong today, and still producing cutting-edge (no pun intended) dental materials and equipment. The huge cache of undestroyed and uncirculated ceramic coins were found in their warehouse located on the site of the former Shofy Kogyo Company in August 2023. They are one-sen coins with a view of Mount Fuji on one side and a cherry blossom on the other.

The company handed over the 15 boxes to the Japan Mint and received an official letter of appreciation and 100 of the coins as keepsakes.

The Mint owns these coins, and we hope that the recent discovery of so many ceramic coins will lead to new discoveries about the circumstances surrounding currency manufacturing at the end of the Pacific War.

In the future, we plan to conduct a detailed investigation into the condition of the discovered ceramic coins while also referring to materials remaining in the Mint’s collection, which we hope will shed more light on the manufacturing conditions at the time.

Once the investigation is complete, the Mint plans to exhibit the coins in the museum at its head office in Osaka as well as at its branches in Saitama and Hiroshima.

* This article was originally published here