World’s oldest mint discovered in China

The world’s oldest known mint coin, which started working between 640 and 550 BC, has been discovered in China.

It produced the first metal ‘spades’ – named for their resemblance to the garden tool – over 2,600 years ago.

The “very well-organized” site was able to mass-produce the first metal currency and helps shed light on the origins of money, archaeologists say.

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The oldest known mint in the world, which started working between 640 and 550 BC, has been found in China. It produced the first metal ‘spades’ coins (shown with the tip reconstructed from a coin shape from the site) – named for their resemblance to the garden tools

View from above: The

View from above: The “very well-organized” site was able to mass-produce the first metal currency, archaeologists said. Pictured is an aerial view of the foundry in Guanzhuang

Previous research has suggested that coins were first issued by merchants, making it much easier to trade, transport and count wealth.  However, the coin in Guanzhuang is located close to the outskirts of the outer city, near the gates to the administrative downtown (photo)

Previous research has suggested that coins were first issued by merchants, making it much easier to trade, transport and count wealth. However, the coin in Guanzhuang is located close to the outskirts of the outer city, near the gates to the administrative downtown (photo)

WHAT IS CARBON DATING AND HOW IS IT USED?

Carbon dating, also known as radiocarbon dating or carbon-14 dating, is a method used to determine the age of an object.

Carbon-14 is a carbon isotope widely used by archaeologists and historians to date ancient bones and artifacts.

The rate of decay of carbon-14 is constant and easy to measure, making it ideal for giving age estimates for anything over 300 years old.

It can only be used on objects that contain organic matter – which was once ‘living’ and therefore contained carbon.

Carbon-14 occurs naturally in the atmosphere as part of carbon dioxide and animals absorb it when they breathe. Animals stop ingesting it when they die, and a finite amount of the chemical is stored in the body.

Radioactive substances all have a half-life, the time it takes for a substance to lose half of its radioactivity.

Carbon-14 has a long half-life, 5370 years to be exact. This long half-life can be used to find out how old objects are by measuring how much radioactivity is left in a sample.

Its long half-life has allowed archaeologists to date objects up to 50,000 years old.

Radiocarbon dating was first invented in the 1940s by an American physical chemist named Willard Libby. He won the Nobel Prize in Chemistry for his discovery in 1960.

They made the discovery during excavations at Guanzhuang, a city and administrative center of Zheng State – a regional power before the rise of Imperial China.

Researchers discovered part of a bronze foundry containing dozens of used and unused coin molds, coin fragments and metal scraps. Together these confirm that this part of the foundry was a coin.

Analysis of the finds shows that the mint was ‘very well organized’ and produced ‘coins of spades’ in a standardized manner.

Spade coins are the oldest known Chinese metal currency and possibly the first in the world, estimated to have been first minted between 750-500 BC.

They were used by the Zheng and surrounding regions until abolished in 221 BC by the first emperor of China.

“The foundry in Guanzhuang started around 770 BC, but initially mainly produced ritual vessels, weapons and tools,” said lead author of the study Dr. Hao Zhao of Zhengzhou University.

“It’s about 150 years later that the minting business appeared in this foundry.”

Radiocarbon dating of the Guanzhuang coin indicates that it started working sometime between 640-550 BC.

This places it early in the history of the spade coin and means that the coins found at the site are the oldest examples of metallic currency ever discovered in China. Although other early mints have been found, no radiocarbon dating has been made.

Researchers hope this new site, located in Henan Province, can shed light on the chronology of money and how it evolved.

Previous research has suggested that coins were first issued by merchants, making it much easier to trade, transport and count wealth.

However, the Guanzhuang Mint is located close to the outskirts of the outer city, near the gates to the administrative downtown.

This could indicate that the government was involved in the early history of currency, archaeologists think, although the limited number of artifacts found at the site means the exact links to the foundry cannot yet be confirmed.

Archaeologists made the discovery during excavations at Guanzhuang (pictured), a city and administrative center of Zheng State - a regional power before the rise of Imperial China

Archaeologists made the discovery during excavations at Guanzhuang (pictured), a city and administrative center of Zheng State – a regional power before the rise of Imperial China

Spade coins are the oldest known Chinese metallic currency and possibly the first in the world, estimated to have been first minted between 750-500 BC

Spade coins are the oldest known Chinese metallic currency and possibly the first in the world, estimated to have been first minted between 750-500 BC

Researchers hope this new site, located in Guanzhuang, Henan Province, can shed light on the chronology of money and how it evolved

Researchers hope this new site, located in Guanzhuang, Henan Province, can shed light on the chronology of money and how it evolved

Radiocarbon dating of the Guanzhuang coin indicates it started working sometime between 640-550 BC

Radiocarbon dating of the Guanzhuang coin indicates it started working sometime between 640-550 BC

Although the mint at Guanzhuang was a later addition, it proved so successful that special mint coins were subsequently built elsewhere in China.

For the next 2,000 years, money would be the copper industry’s main output.

“Coin-making was one of the most revolutionary financial innovations in human history,” said Dr. Zhao, adding that wealth could be easily traded, counted and hoarded.

The radiocarbon dating used by archaeologists, also called radiocarbon dating or carbon-14 dating, is a method used to determine the age of an object.

Analysis of the finds reveals that the mint was 'very well organized' and produced 'spades' coins in a standardized manner

Analysis of the finds reveals that the mint was ‘very well organized’ and produced ‘spades’ coins in a standardized manner

Spade coins are the oldest known Chinese metal currency and possibly the first in the world

Spade coins are the oldest known Chinese metal currency and possibly the first in the world

It is estimated that they were first minted between 750-500 BC, according to researchers

It is estimated that they were first minted between 750-500 BC, according to researchers

The coins were used by the state of Zheng and the surrounding regions until they were abolished by the first emperor of China in 221 BC

The coins were used by the state of Zheng and the surrounding regions until they were abolished by the first emperor of China in 221 BC

Carbon-14 is a carbon isotope widely used by archaeologists and historians to date ancient bones and artifacts.

Earlier this week, archaeologists also revealed that they had used radiocarbon dating of human remains to determine that the famous Inca site of Machu Picchu is decades older than previously thought.

The research suggests it was in use in 1420 — more than 20 years earlier than scientists had expected.

Machu Picchu was built as an estate for Emperor Pachacuti, who, according to historical records, rose to power in 1438 before conquering the area where the site is located.

This had led experts to believe it was built after 1440 and perhaps as late as 1450.

The latest research is published in the journal antiquity.

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