1835 to 1870 Japan - Tenpō Currency – Unusual Shape 100 Mon Coin

The Tenpō Tsūhō (天保通寳) is one of Japan’s largest and most distinctive Edo-period coins, instantly recognizable for its unusual oval shape with a square hole. Issued under the Tokugawa Shogunate during the Tenpō era, it bears Tenpō Tsūhō (“Tenpō Currency”) on the obverse and 當百 (“Equal to 100”) on the reverse, alongside the official mint mark.

Cast in bronze with a distinctive antique texture, the coin represents the late Edo monetary system and Japan’s transition toward the modern Meiji era.

 Presented in a Display Frame, accompanied by an informative background card depicting traditional Japanese art and historical context.

Coin Specifications:

• Face Value: 100 Mon
• Weight: 20.7 g
• Diameter: 49 mm (oval)
• Metal: Bronze (Cu 78%, Pb 12%, Sn 10%)
• Cast Finish
• Mint: Honza (Edo) & Zen’iza (Osaka)
• Mintage: ≈ 484 Million