China
Qing Dynasty, Emperor Sheng Zu Pattern 5 Cash ND (1662-1722) F-VF, Board of Works, Design similar to Hartill-22.93, but "Dang Wu" added to the reverse to convert a 1 Cash coin to a 5 Cash coin, 25mm, 5.42gm. Obv. Kang Xi Tong Bao. Rev. Boo. Yuwan Dang Wu. During this period, the price of copper had risen dramatically, and the mints were losing huge amounts of money. It's possible that this was a proposal to increase the value of the mint's copper by adding a "5" to the 1 cash coins and passing them as 5 cash. This did not happen, and this piece seems to have never actually been issued, and is quite rare.From The Valley View Life Collection
Estimate: 500-700 USD