1 Cash - Yongzheng Tongbao, Boo-ji

The Boo-ji mint — the Board of Revenue facility in Beijing — was one of two central government mints operating under direct imperial supervision, the other being the Board of Works mint across the city. Production at Boo-ji was tightly regulated, with strict quotas and metal alloy ratios enforced by imperial edict. The Yongzheng emperor was notably obsessive about standardization, issuing repeated directives throughout his reign to clamp down on underweight casting and alloy adulteration that had plagued the Kangxi issues before him.

The 1729-1730 window corresponds to the final years of Yongzheng's reign before his death in 1735, when output at both Beijing mints was being closely audited.