Ōban

An Ōban (大判) was a monetary ovoid gold plate, and the largest denomination of Tokugawa coinage. Tokugawa coinage worked according to a triple monetary standard, using gold, silver and bronze coins, each with their own denominations.^[1]

The first Oban – Tenshō Ōban (天正大判) – were minted by the Gotō family under the orders of Hideyoshi in 1588.^[2]

The Tenshō Ōban was equivalent to ten Ryōs, or ten Koban (小判) plates, with a weight of 165 g.

Notes

^ Metzler p.15
^ The Cambridge History of Japan: Early modern Japan by John Whitney Hall p.61 [1]

References

Mark Metzler (2006). Lever of empire: the international gold standard and the crisis of liberalism in prewar Japan. Vol. Volume 17 of Twentieth Century Japan: The Emergence of a World Power. University of California Press. ISBN 0-520-24420-6. {{cite book}}: |volume= has extra text (help)

[1] Metzler p.15

[2] The Cambridge History of Japan: Early modern Japan by John Whitney Hall p.61 [1]

[1]

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