5 Zhu ("Western Han" type; with half-moon)

The 5 Zhu coin was introduced by Emperor Wu of the Western Han dynasty in 118 BC to stabilize the Chinese currency system, which had suffered from private minting and inconsistent quality. By centralizing production under the Superintendent of Minting, the Han government established a standardized circular shape with a square hole, a design that would remain the hallmark of Chinese coinage for over two thousand years. The specific variety featuring a 'half-moon' or crescent mark on the reverse is often interpreted by numismatists as a minting inspector's mark or a technique to facilitate the filing and finishing of the coin edges during the manufacturing process.

The minimalist design of the 5 Zhu—bearing only the characters 'Wu' and 'Zhu'—reflects the administrative pragmatism of the Han era, prioritizing utility and state control over ornate decoration. These coins were cast in bronze using sand molds, a labor-intensive process that allowed for mass production across the empire. The 'half-moon' variants are particularly prized by collectors today for the insight they offer into the evolving technological practices of ancient Chinese foundries, representing a period where the state sought to unify the economy through a singular, recognizable aesthetic.