Coins are another important archaeological source of history of ancient India. Hoards of gold, silver and copper coins have been unearthed in different parts of the country which provide us valuable information regarding Indian history till the Gupta age (6th century CE). The study of coins is known as Numismatics.
Numismatic evidence, though comparatively less important than its inscriptional counterpart, forms a very authentic source of information on certain periods of ancient India. It can be broadly divided into two distinct periods: pre and post-Mauryan period. Coins in the period prior to the Mauryas are generally of two types: the punch-marked coins and the coins cast in die. These coins were issued both by the monarchical and the republican states, on the one hand, and by private merchants, trade guilds, city corporations and other small private bodies on the other. The earliest coins, made mostly of silver and, in a much lesser quantity, of copper, were the punch-marked coins, which did not contain any name but figures and symbols only. These coins were made by imprinting symbols on the obverse and reverse by individual punches. We also come across uninscribed cast copper coins and punch-marked coins with symbols. These were made by pouring molten metal in casts bearing the negatives of these designs. It is not till after the Greek invasion that we come across coins with the names of kings clearly engraved on them. The history of the Bactrian, Parthian and Scythian princes in India has been reconstructed almost solely on the basis of a careful study of the coins issued by them. These coins contained the busts and the names of the rulers.
A large number of coins of the Saka rulers also contained the dates according to the Saka era thereby enabling the historians not only to draw dynastic lists but also to determine the chronology of the ruling powers. Thereafter, plenty of gold coins of the Kushana and Gupta rulers are also available. The Kushanas continued the tradition of bilingual (Greek and Khroshthi) inscriptions but their coinage also displays Iranian and Indian influence. The number of coins belonging to the postGupta period is severely limited. The coins of great emperors like Harsha or ruling dynasties like 12 the Chalukyas, Rashtrakutas, Pratihara, or Palas, not to speak of lesser kings and dynasties, are either unknown or of little significance. Coins have helped us in finding out the names and dates of various rulers besides helping us indirectly in assessing the economic and religious conditions of the times when they were issued.
Some historians have endeavoured to ascertain the economic condition of India at different times by scientifically examining the gold, silver and copper coins issued during the concerned periods. The coins provide us information about personal traits of the rulers and the deities they worshiped. Besides giving us an idea about the extent of the empire of a ruler, coins can enlighten us on the various kinds of art and its development, such as the art of writing, the art of moulding metal etc. Moreover, coins are also a principal source of our information regarding the various Indian states, both monarchical and republican, that flourished during the ancient period. The history of the Mitra rulers of Panchala, Malavas, and Yaudehas has been almost exclusively reconstructed on the basis of their coins.
Finally, coins in several ways, supplement the information acquired through literature. Many a time, the coins alone have brought to light certain rulers who were not mentioned anywhere in the literature. For example, in our literature, there is a mention of only three or four Greek rulers in India, where as about thirty-three such rulers ruled in India for two centuries.
In addition to coins and inscriptions, we have other archaeological remains in the form of buildings, pottery, statues of stones, etc. which help us in tracing the history and evolution of Indian art. The excavations at Harappa and Mohenjodaro tell us that long before the Aryans, there flourished an advanced civilization in the valley of the Indus. The systematic excavations of the ancient sites like Taxila or the monastic establishments at Sarnath have thrown light upon Buddhist way of life. The stone temples in south India and the brick monastaries in Eastern India still remind us of the great building activities of the past. The Megaliths reveal the way of life of the people in the Deccan from the Iron Age onwards.