From Fragmentation to Standardization: The Pre-Qin Monetary Landscape

Before the Qin dynasty’s unification in 221 BCE, China’s Warring States period (475–221 BCE) witnessed a chaotic monetary system where seven major states issued distinct currencies. Archaeological evidence reveals four primary forms:

– Spade Money (布币): Dominant in Zhou and Jin territories, featuring hollow-handle (空首布) and flat-handle variants with measurement units like “jin” (釿)
– Knife Money (刀币): Used in Qi and Yan states, inscribed with the denomination “hua” (化)
– Ant Nose Coins (蚁鼻钱): Turtle-shell-shaped bronze tokens circulating in Chu alongside gold plates
– Round Coins: The Qin state’s innovation—circular with square holes, precursors to later Chinese cash

This monetary Tower of Babel reflected political divisions but also growing commercial needs, as cross-state trade prompted some regions to adapt foreign currencies. Excavations show hybrid cases like:
– Qi state producing limited round coins with square holes (賹化)
– Yan state minting occasional spade coins
– Jin territories adopting round coins alongside traditional spades

The Qin Monetary Revolution: Standardization as Statecraft

Upon unifying China in 221 BCE, Qin Shi Huang implemented radical currency reforms documented in the Records of the Grand Historian:

1. Two-Tier System:
– Upper currency: Gold measured by yi (镒, ~20 oz)
– Lower currency: Bronze Ban Liang coins inscribed “半两” (half liang)

2. Legal Prohibitions:
– Demonetized pearls, jade, shells, silver, and tin
– Criminalized private minting

3. Physical Standardization:
– Circular form with square hole (symbolizing heaven-earth cosmology)
– Standard weight: 12 zhu (铢, ~7.5g)

Decoding the Ban Liang: Archaeological Discoveries

Extensive excavations reveal the coin’s evolution:

### Early Warring States Phase (Pre-221 BCE)
– Sites: Sichuan’s Qingchuan tombs, Shaanxi’s Yongcheng
– Characteristics:
– Diameter: ~3.1 cm (1.2 Qin inches)
– Weight: 5.4–8 zhu (~4–6g)
– Archaic script with short horizontal strokes in “半两”
– Irregular edges, no rim

### Unified Qin Standard (Post-221 BCE)
– Key Findings:
– Xianyang Capital: 170 coins across palace sites showing 3 size grades (2.3–3.1 cm)
– Terracotta Army Pits: 600+ coins ranging 1.9–6.5g
– Great Wall Sites: Inner Mongolia discoveries proving nationwide circulation

– Technical Advances:
– Smoother edges, standardized square holes
– Xiaozhuan script with balanced character strokes
– Narrower casting sprues indicating improved minting

The Minting Process Revealed: Discovery of Coin Molds

Archaeological finds of Ban Liang molds demonstrate centralized production:

1. Afang Palace Mold (Xi’an):
– Bronze master mold for 6 coins
– Precision engraving matching Inner Mongolia hoards

2. Guichi County Finds (Anhui):
– 23-coin capacity molds
– Evidence of southern minting centers

3. Sichuan’s Sandstone Mold:
– 28-coin capacity
– Shows Qin’s economic expansion into conquered territories

Economic Impact and Social Legacy

The Ban Liang system facilitated:

1. Market Integration: Standard pricing across former warring states
2. Taxation Efficiency: Unified currency enabled bureaucratic management
3. Cultural Unification: Coin inscriptions promoted standardized script

However, late-Qin inflation saw:
– Reduced coin sizes (2.6–2.8 cm)
– Emergence of “elm seed” (榆荚) lightweight coins
– Increased private minting

Enduring Influence on Chinese Numismatics

The Ban Liang established core features that persisted for 2,000 years:

1. Circular/Square Hole Design: Maintained until 19th century
2. Weight-Based Naming: Later coins like Wu Zhu (五铢) followed this principle
3. Centralized Minting: Han dynasty perfected the system

Modern excavations continue to reveal how this monetary revolution underpinned China’s first centralized empire—a testament to the Qin’s vision of unification that still echoes in today’s RMB.