koban

(from the article `coin`) ...a gold and silver coinage since the 16th century. The gold coins are large flat pieces in the shape of rectangles with rounded corners, the ...
Found on http://www.britannica.com/eb/a-z/k/42

Koban

[coin] The 小判 was a Japanese oval gold coin in Edo period feudal Japan, equal to one ryō, another early Japanese monetary unit. It was a central part of Tokugawa coinage. The Keichō era koban, a gold piece, contained about one ryō of gold, so that koban carried a face value of one ryō. However, successive mintings of the koban had v...
Found on http://en.wikipedia.org/wiki/Koban_(coin)

Koban

An oval coin, usually gold or silver
Found on http://www.wafuku.co.uk/glossary.htm
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