100 Mon Tenpo Tsuho Coins - 天保通寳 - "Currency of the Tenpo Era"
Cast from October 1835 to 1870, the Tenpo Tsuho (or Tempo Tsuho, as it is pronounced) is one of the most iconic Japanese Edo-era cast coins because of its large size, oval shape and good casting. These coins are made from bronze, have Tenpo Tsuho on the front (meaning currency of the Tenpo era) and To Hyaku (Value 100) and the mint official's signature on the back. The edges are stamped with Sakura (cherry blossoms) of various shapes and sizes depending on the mint (a mint mark, or shirushi, 印). Interestingly, Tenpo Tsuho are widely known even to non-coin-collectors due to their nature as being luck charms.

Satsuma issue in high grade

Rare Akita issue made with a higher percentage of copper

Mints and Varieties

There are many very difficult to identify varieties of 100 Mon, and several specialized Japanese works have been published on the subject. The most common coins are from Honza (Edo, Musashi province) and Satsuma, and these are only worth a few dollars to $20 depending on the condition. However, some rare and therefore more valuable varieties exist for those willing to spend the time identifying these oval coins! The Hartill catalog lists eight varieties; the JNDA catalog lists 24; the Jones catalog lists 22. Furthermore, some Japanese catalogs are entirely devoted to Tenpo Tsuho.

Fun Fact

In the 1950s, one Japanese candy manufacturer, Glico, decided to give out Tenpo Tsuho coins as prizes for buying their boxes of caramel. However, Glico depleted their supply of real coins to use, and began making nearly identical replicas! These coins have deeper cut characters than the regular 100 Mon, look like medals, and do not have any filing marks. Interestingly, these replicas carry a premium over regular 100 Mon due to their unusual origin!