10 Cash - Xianfeng Zhongbao, Boo-di, Urumchi, small size

The Boo-di mint at Urumchi operated under extraordinary logistical pressure during the Xianfeng reign — supplying coinage to Xinjiang required crossing thousands of miles of steppe and desert, and the chronic copper shortages that plagued mints across the empire were felt here more acutely than almost anywhere else. The "small size" designation within this type reflects deliberate weight reduction as the Qing administration struggled to maintain output during the Taiping and Nian rebellions, which were simultaneously draining both treasury reserves and military copper stocks.

Within a few years of this issue, the Muslim rebellions of the 1860s would destroy the Urumchi mint entirely.