South Asia is the cradle of human civilization for a very long period of time. The river basins of north and north western India have experienced human occupation since 5000 BCE. These people did not live isolated. They engaged in trade and commerce with people from other regions such as Central Asia and Arabian Peninsula. The earliest trading activities were conducted through barter. But with the advent of more complex economic transactions the coins became the medium of commercial exchange.
The earliest reference to coins in the context of south Asia can be found in the Vedas. However, the archaeological findings suggested that the earliest instances of coin circulation in India can be traced back to 6th-5th century BCE. These earliest coins are known as the famous ‘punch-marked’ coins.
The punch-marked coins were mainly made of silver. There were copper punch-marked coins too. These coins are mostly of rectangular shape, occasionally square or round. These coins have been found in large numbers in various places of northern India ranging from the Taxila-Gandhara region of north western India to middle Ganges valley.
The process of making these coins was quite interesting. The coins were cut from large metal sheets. Sometimes metal globules were also flattened to shape them as coins. Next, the symbols were inscribed on the coins using dies or punches. These coins did not show any great artistic or aesthetic excellence in their appearance. This was because they were the earliest attempts of coin minting in India. There shapes were also mostly irregular, but they showed excellence in maintaining the weight standard of the coins. The majority of the punch-marked coins made of silver weighed about 56 grains or 32 rattis. The weight-system of the punch-marked coins as well as all the other ancient Indian coins was based on the red and black seeds of a particular variety of tree called Abrus precatorius. The weight of these seeds was known as the rattis. The uniformity of the weight system was one of the main reasons behind the long usage of these coins over a vast area of South Asia.
These coins did not bear any inscriptions on them. Instead they carried symbols of geometric designs; natural bodies such as sun, moon, mountains; depictions of different animals and plants, etc. Some of them also carried human figures. These punch marks are not properly inscribed in all the coins and some of them have become illegible by now. The significance of all these symbols inscribed on the coins could not be ascertained by the numismatists with certainty. They may have some political or religious importance.
The coins of this variety which were circulated in northern India were categorized into four main series by the numismatists. They divided the coins in different series based on their weight, the nature of the symbols inscribed, and their area of circulation. In the distant hilly terrains of Taxila-Gandhara, the punch-marked coins were a little heavier and carry a single symbol. In the Kosala region of middle Ganges valley, the coins were also of heavy weight nature but came with multiple punch-marked symbols. In the Avanti region of western India light weight single punch-marked coins were in use. Magadha, a powerful state in eastern India issued their own punch marked coins with a light weight standard carrying multiple symbols. With the political ascendancy of Magadha in the 3rd and 2nd century BCE, the Magadhan punch-marked coins became the most circulated coins in South Asia. It also shows the importance of studying the numismatic trends in grasping a proper understanding of ancient Indian history.