1 Cash - Xianfeng Tongbao, Boo-kiyan, large type

The Board of Revenue Mint in Beijing — Boo-kiyan in Manchu romanization — was one of two central government mints operating in the capital during the Xianfeng reign, the other being the Board of Works. Large-type cash of this period were produced as the Qing fiscal system was coming under severe strain from the Taiping Rebellion, which erupted in 1851 and would ultimately force the court into drastic monetary debasement within a few years of this coin's production window.

By 1854 the same mint was striking iron and lead cash and issuing enormous nominally-valued pieces worth up to 1000 cash — a direct consequence of war expenditures overwhelming conventional bronze production.