Known in Japan as Nagasaki Boeki Sen (which translates to Nagasaki Trade Coins), these copper coins were issued
from the 14th of July 1659 (Manji era year 2) until 1685. These coins were imitations of Chinese coins, and they bear the
inscription "Genho Tsuho," or Yuanfeng Tongbao in Chinese. However, it is easy to tell the Japanese and Chinese
(as well as the Vietnamese imitations, which are more crude) coins apart due to their (significantly) different calligraphy.
The Hartill catalog lists eight varieties,
whereas the Jones catalog lists thirteen. It should be noted that there are also Japanese Nagasaki Trade coins with
different inscriptions than the common "Genho Tsuho" coins. These are both more valuable and are harder to tell apart
from the Chinese and Vietnamese coins that they imitate.