The implementation of a real monetary system in Japan is due to Toyotomi Hideyoshi, a fundamental figure in the history of the Rising Sun country. Whereas until the fifth century, barter was the main means of trade in Japan, commerce with China led to the use of coins, and to coinage similar to that of China. However, the continued scarcity of raw materials for the coins and the country’s inside divisions hindered the development of this first attempt at a new coinage. As a result, in the XII century, Chinese coins became Japan’s only real currency, and remained so until the sixteenth century, notwithstanding some local initiatives.

And it was Toyotomi Hideyoshi, the great unifier of Japan under a single leader as well as the owner of many gold and silver mines, who restored the use of Japanese coins. This is the period in which the first gold coins were used; in fact, before Hideyoshi, gold was used as a form of payment but only as grains or leaves. In 1588 the Ōban, also known as the Tenshô-hishi-ôban, was minted, to date one of the largest coinages in the world and one of the rarest coins: it is an oval gold slab, 10 centimeters wide and 17 long and weighs over 150 grams. Starting in 1601, with the beginning of the Edo period, the Shogun Tokugawa Ieyashu rationalized his predecessor’s project, broadening the monetary system by introducing smaller gold coins known as the Koban, with silver and bronze standards minted alongside the gold issue. The system was based on the Ryō unit of weight (about 16.5 grams). The first coinage had an 85% gold content, but inflation led to amounts diminishing down to 57% at the end of the seventeenth century during the Genroku era. At the beginning of the Hōei era, the gold content returned to its initial values but the size of the coins was reduced.

The Ōban and Koban coins are very different from western types for a number of reasons: the first one is surely their oval shape (rectangular for the smallest denominations) and for their size. There were also denominations smaller than the Tenshô Ōban mentioned above, such as the 9x5 centimeter Goryoban or 5 Ryo sold at a Bolaffi auction in June 2015, or the 7x4 centimeter Keicho Koban. The second difference is the presence of markings on the coins known as “Tsuchi Me”, literally “eye”, showing the authority that has issued the coin. The first issues have a variety of coarse markings, but as the engraving techniques improve they are replaced by the Kiri flower, the official symbol of the central authority. Also, coins with markings on both sides are less common. In some cases, on the largest coins, there is writing in black ink that proves its value and the signature of the Goto family, the supervisors of the mint, and that has often been counterfeited in the modern period.

But what were these coins used for? Certainly the largest were used for important domestic and international commercial transactions, mainly for luxury goods or silk from China, but also as gifts for the Empire’s highest dignitaries, given their considerable ornamental value. In fact, it is not unusual to find these coins used as jewellery. In 1871, after a couple of years of meetings and discussions the great modernization of the Meiji period took place. It revolutionized Japan’s entire political and social system and introduced a new monetary system inspired by western models: coins became round and based on the decimal system, as is the current Yen. The previous coinage therefore lost its original function, but remained precious as a gift item, and many copies were made of the originals, considered their rarity.

By Gabriele Tonello