5 Zhu ("Western Han" type; with small Wu)

The 5 Zhu coin was introduced during the Western Han Dynasty under the reign of Emperor Wu in 118 BCE to standardize the erratic currency systems that preceded it. By the time of the issues around 74 BCE, the coin had become the quintessential symbol of Han economic authority, featuring a circular shape with a square hole to facilitate stringing for transport. The design was remarkably stable, designed to be durable and easily recognizable across the vast, expanding territory of the Han Empire.

These coins were produced through sand-casting, a process that utilized clay molds to create multiple units at once. The specific variation known as the 'small Wu' type is often associated with the later years of the Western Han or early regional minting variations, reflecting the practical efforts of the imperial government to maintain a consistent money supply amidst fluctuating economic conditions. They were received as the bedrock of domestic trade and are now regarded as a vital primary source for understanding the centralization of power in ancient Chinese history.