Keicho- chogin (Silver oval coin) (慶長丁銀)
Keicho-chogin is a kind chogin (collective term of silver) which started to be minted in July 1601, the beginning of Edo period, and it is a silver coin by weight standard as well. The keicho- chogin and keicho- mameitagen (keicho is the name of era in Edo period) are collectively called by keicho-gin.
They are also called by keicho-kingin (gold and silver) along with Keicho oban, Keicho koban, and Keicho ichibuban.
At front side, hallmarks of "(image of Daikokuten), joze" and "joze, ho" were inscribed from several or more than 10 places. As the image of Daikoku inclines a little, it is distinguished from shotoku chogin with the image facing the front. The last two strokes of "是"were long. The junimen-daikoku chogin where daikoku by 12 phases were inscribed were for taxation to Edo bakufu(Japanese feudal government headed by shogun) or celebration.
The daikoku chogin in the beginning was thin since it was cut appropriately where many hallmarks were inscribed and forms were various and simple with small charactesr. The daikoku chogin in the latter period were similar to genroku- chogin in its form where daikoku hallmarks were inscribed at two places at top and bottom as well as six places at both sides totaling eight hallmarks. In Keicho era (1596-1615), 16,000 kan (unit of weight) of silver was contributed to ginza (history)(organization in charge of casting and appraising of silver during Edo period), but in 1694 when silver production in Japan was reduced, total cupellated silver contributed to ginza was 5,090 kan in total including 1,973 kan of kogi (shogunate) cupellated silver and 3,297 kan of kai (buying) cupellated silver from feudal lords, and in the latter period when the form was regulated,.the remaining amount of silver declined in accordance with the production amount.
In May 1601, based on the suggestion by Shouemon GOTO (there are two theories that he was the same as Shozaburokoji GOTO of kinza and he was a different person) and kanbe SUEYOSHI, wealthy merchant in Hirano, Settsu Province, Ieyasu TOKUGAWA decided that Sakube YUASA in Sakai was Daikoku-Joze, and ginza was established in Fushimi, Kyoto with Joze as its head where keicho- chogin started to be minted (there are several theories about establishment period). Prior to issuance of keicho- chogin, workmen in Nanryoza in Sakai presented Kiku-ichi-monji-ingin (Ichimoniji is trims above and below the artwork of a hanging scroll), ebisu-ichi-monji-ingin and kukurihakama-chogin as a sample to Ieyasu, and kukurihakama-chogin where hallmark of Daikokuzo was inscribed was selected, and it was established as original of keicho-chogin. In addition to "daikokuzo","joze" and "ho", omodaka-chogin where hallmark of family crest of ichiran-omodaka was inscribed was regarded to be the trial of minting coin in the beginning.
This chogin was a flat "namako" type silver mass where silver and bronze were mixed, upon which hallmark of "joze", "ho" and Daikokuzo" were inscribed. Standard of weight was a piece of silver, which is 43 monme (unit of weight), that is about 161 grams, but actually it ranged from 20 monme, that is about 75 grams, to 60 monme, that is about 225 grams, and it was used for trading after determinig the amount by weight.
The unit of currency of silver by weight standard was ginten (ten is 10) ryo where 43 monme was a piece of silver before Azuchi- Momoyama Period, but it was used mainly for giving prize. After the silver coin started to be used actively for trading from Genki and Tensho era, kan (unit of weight) and monme were used frequently. In Edo period, kan and momen were mainly used to express the weight such as silver by what monme (silver by what kan), which was called ginmoku, and since silver coins were used by weight standard as a currency of merchant, trading was conducted mainly by silver.
Since silver by weight standard needs many works by weighing at each trade, at ginza and currency exchange, it was defined to be a piece of silver (43 momen) for giving as prize and 500 momen for trading, where it was used as "gold and silver by wrapping" that was wrapped by Japanese paper with seal.
As they were called by "using silver by kamigata (kinki region including Kyoto and Osaka)", chogin and mameitagin were used not only in western Japan centering around Osaka but also along Sea of Japan in Hokuriku and Tohoku region. In unification of the currency, it was Ieyasu TOKUGAWA's ambitious strategy to show people that he was a ruler of the country facilitating the smooth unification of the country, by way of taking over the system in which silver by weight standard had been widely used among merchants centering around Osaka, as well as distributing the keicho-chogin in Kamigata (Kyoto and Osaka area), the base of Hideyori TOYOTOMI. The reason that silver by weight standard was widely accepted by merchants are as follows; 1. Rationality where value is defined by standard 2. Convenience where calculation is made by decimal method by the unit of "kan","monme" and "fun"(unit of weight) 3. Trade with China, where ginjo (silver mass called by gincho and cupellated silver) such as batei-gin was the main currency for trading by high price, was frequently conducted. Another reason is that there were some silver mines including Ikuno Silver Mine, Inaba Silver Mine, Tada Silver Mine and Tsushima Silver Mine as well as Iwami Ginzan Silver Mine in western Japan, and there was an abundant supply of cupellated silver produced by shiborigin (kind of silver) from rough bronze at Osaka Bronze Production.
The ideal of bakufu was to use solely keicho-gin by unification of weight standard in place of currency of daimyo's territory such as kocho-gin and gokuin-gin that had been used before that, but keicho-gin was not distributed as far as local areas since a large amount of money was distributed to foreign countries as a result of payment of trade, and thereby they had to wait for arrival of genroku-gin for unification of currency. In the first half of 17th century, a large amount of cupellated silver such as soma silver (Sama, iwami Province), nagito silver (Nagato Province), seda silver (Sado Province) and tajima silver (Tajima Province) was exported, and bakufu, in principle, prohibited export of good quality cupellated silver by the Order of 1609 and decided that settlement was made by keicho-chogin whereas although ratio of export of cho-gin and cupellated silver was unknown by frequent illegal export of cupellated silver, many of ishu-gin that had been proud of producing largest amount in the world was minted to keicho-gin and then exported.
In April 1697, the bakufu ordered that the use of keicho-gin be stopped by March 1698; however, many people hoarded them instead of exchanging them, so in January 1698, the bakufu ordered that its use be stopped by March 1699, but to no avail. Finally it was stopped at the end of April in 1738.
Chogin in the beginning of Keicho era was cut by chisel in accordance with trade price, but in order to stop it, in 1620, Edo bakufu started to mint mameita-gin (small silver) composed of flat particle whose karat was the same as chogin (0.1 to 10 monme), and prohibited its cutting by chisel thereafter. This mameitagin was used for adjusting small amount and small trading, and played a supplementary role of chogin.
Keicho-mameitagin was minted at the same karat as keicho-chogin where hallmark of "(daokokuzo) joze" or "joze, ho"were inscribed, and daikokuzo inclines a little, which is similar to chogin. Many of keicho-mameitagin were deformed. There were large coins where several hallmarks of daikokuzo were inscribed, and it was also said that there was no "daikokuzo at both sides"where hallmarks were inscribed at both sides, but it was confirmed to have existed.
Karat of keicho-gin
The karat by regulation was 80% by silver (discounted by 12%) and 20% by bronze..
The rate of gold and silver contained in the coin in Edo period was confidential, and it was strictly prohibited to analyze the coin by ordinary citizen. However, the rate of containment for gold and silver was very important information for money changer, and it was analyzed in secret, and the mechants knew the result. The quartz was not useful in the analysis of karat of silver, but those who were well versed in it such as appraiser of silver and money changer determined the karat by eutectic composition that was seen in rust on the surface and crack.
The rate of silver contained was listed by exchange rate of silver and keicho-chogin in ginza.
For example,cupellated silver that was the best silver (pure silver) by refining method at that time was bought by keicho-chogin by adding 10 % in ginza, and it was called "10% addition". By this standard, the same karat as keicho-gin, which was 80% of the cupellated silver, was 1.1X0.800.88 where it was bought by 0.88 of the weighted value of chogin.. This is called metal by "discounting 12%". This 12% is the fee for minting coin in ginza.
In Meiji period, the coin of Edo p;eriod was analyzed by Minting Authority in Japan. The keicho-gin was described as follows.
Most of the miscellaneous part was bronze, but small amount of lead and bismuth was included as well.
Minting amount of keicho-gin
The coin in Keicho era (koban and chogin) was called "temaefuki"where maker of gold and silver handiworks obtained the metal by himself, delivered to kinza and ginza after processing it in the form of coin, and issued after the hallmarks were inscribed. There is no record of exact minting amount of keicho-koban since historical record including "Ginza Kakitome" (record of ginza) was lost by Fire of Meireki.
However, by the amount distributed to foreign country as trade settlement estimated by Hakuseki ARAI later and value estimated by reminting to genroku-kobangin, total of chogin and mameitagin were 1,200,000 kan (about 4,500 ton).
"Getsudo-kenbunroku"(record of society from 1679 to 1734) says that minting amount was a little more than 350,000 kan (about 1,310 ton), but it is doubtful considering the amount of keicho-gin that was distributed to foreign countries.
When kogi (shogunate) cupellated silver paid by silver mine of tenryo (shogunal demesne) was entrusted to ginza, they made chogin from it and their income, buichi-gin, was determined to be 3% of the minting amount, while remaining part was paid to bakufu.