Moneta Giappone Koban (1 ryo) - Tempo era (1837-1858)

A "koban" was a unit of Japanese currency made of gold that was used during the Edo period in Japan (1603-1868). During this time, Japan was under the control of the Tokugawa shogunate, and the monetary system was heavily regulated and controlled by the government.

The koban was a rectangular gold coin, weighing around 11 to 18 grams, typically bearing the seal of the shogun and other inscriptions in kanji. It was used for high-value transactions and was considered the primary gold currency unit of the time.

Kobans held significant value and were widely accepted for commercial transactions and exchanges of goods and services. However, as Japan opened up to Western influences towards the end of the Edo period, the Japanese currency evolved to include other types of coins, including foreign currencies.