Archaeologists have uncovered 2,640 to 2,550 year old clay molds for casting pike pieces as well as fragments of finished pike pieces at Guanzhuang in Xingyang, Henan Province, China. The technical characteristics of the molds demonstrate that the site – which was part of the bronze foundry of the Eastern Zhou era (770-220 BCE) – operated as a workshop for manufacturing standardized parts.
“The origins of metallic money and the monetization of ancient economies have long been a subject of research in both archeology and economic history,” said Dr. Hao Zhao of the School of History of Zhengzhou University. and his colleagues.
“It is believed that the first coins were minted in China, Lydia (western Asia Minor) and India. “
“Of these, the hollow-handled spade coin (kongshoubu) minted in China is a likely candidate for the first metal coin.”
“The pike piece was an imitation of practical metal pikes, but its thin blade and small size indicate that it had no utilitarian function.”
“The first spade coins had a hollow, fragile socket, reminiscent of a metal shovel. This socket was made into a thin, flat coin in later coins, and over time characters were applied to the coins to mark their denominations.
“Several versions of pike coins circulated in the central plains of China until their abolition by the first Qin emperor in 221 BCE.”
“Their origin and ancient history, as well as the social dynamics in which they were developed, remain controversial, however – a situation parallel to the century-long debate over Lydian coins.”
Dr Zhao and his co-authors at Zhengzhou University and Peking University have uncovered ancient remains from different stages of the minting process in Guanzhuang in China’s Henan Province.
The workshop was part of a well-organized and integrated bronze foundry operated under the auspices of Zheng State.
“Guanzhuang is located in the central plains of China, about 12 km south of the Yellow River,” archaeologists said.
“Continuous excavations since 2011 have revealed the general layout of a town, which consisted of two walled enclosures and moats.”
“The city was founded in c. 800 BCE and abandoned after 450 BCE.
“The excavations between 2015 and 2019 revealed a large area of artisanal production in the center of the outer enclosure, just outside the south gate of the city center. This area included workshops involved in the production of bronze, ceramics, jade, and bone artifacts.
“The bronze foundry occupied the largest area. Its main features include more than 2,000 pits for dumping production waste, most of them between 1.5 and 3 m in diameter, with a depth of 1 to 2.5 m.
“Alongside the ceramic shards, these pits contained abundant remains related to bronze casting activities, including crucibles, ladles, bronze droplets, unfinished or broken bronze artefacts, clay molds, coal of wood and fragments of furnace. “
At the site, researchers found two fragments of finished pike pieces, named SP-1 and SP-2.
“The SP-1 piece is so well preserved that its complete form can be reconstructed with confidence,” they said.
“This example is a typical pointed shoulder spade piece, with an overall (restored) length of 14.3 cm, a shoulder width of 6.35 cm and a maximum thickness of 0.9 mm. The weight of the existing part is 27.1 g.
“Reconstruct the volume of his missing feet to about 660 mm3 (4-5g), we estimate that the original weight of the SP-1 was not less than 31g, including the weight of the clay core inside the handle.
As is typical of early pike coins, there is no inscription indicating the name of the locality where the coin was cast or its face value.
“The SP-2 coin was found in the context of the Eastern Han Dynasty (200 CE), and therefore the coin must be considered a residual find, as the pike coins had long since been abolished at this time. era, ”they said.
“Of this piece, only the handle and its clay core survive. They are exactly the same shape and size as the corresponding portions of SP-1.
Analysis of the composition shows that the copper content of SP-1 and SP-2 is 62.5 and 76.46%, respectively.
“The existence of a minting activity in Guanzhuang is further documented by numerous discoveries of clay cores and outer molds for casting coins,” the scientists said.
“All the molds are made of fine reddish silt, which was also the main material for producing clay molds for casting other types of bronze products at the Guanzhuang foundry.”
Combining evidence from radiocarbon dating, mold style, and ceramic typology, they suggest that the Guanzhuang foundry was first established around 780 BCE.
During its initial phase of around 150 years, the foundry primarily produced ritual vessels, weapons, and tank accessories – items used in ceremonies, warfare, and other aspects of elite life.
Standardized minting started from the second phase of the Guanzhuang foundry, after c. 640 BCE and no later than 550 BCE, and he used the workshop’s existing bronze production capacity.
“Currently, Guanzhuang is the oldest known archaeological coin site dated by robust radiocarbon dates in the world, and the SP-1 coin is the first spade coin – and, more generally, the first Chinese coin – recovered. in a secure archaeological context, “said the authors.
“The striking techniques used in Guanzhuang are characterized by batch production and a high degree of standardization and quality control, which indicates that the production of pike pieces was not a sporadic small-scale experience, but rather a well-planned and organized process in the heart of the central plains of China.
The team’s article was published this week in the journal antiquity.
Hao Zhao et al. Radiocarbon dating of an ancient minting site: the emergence of standardized coinage in China. antiquity, published online August 6, 2021; doi: 10.15184 / aqy.2021.94