Read this article to learn about the Iron Age: The Second urbanisation in India:
The period of second urbanisation (6th century B.C. to 3rd century B.C.) noticed large-scale beginning of town life in the middle Gangetic basin.
The widespread use of iron tools and weapons helped the formation large of territorial states.
The towns became good markets and both artisans and merchants were organised into guilds under their respective headmen.
Eighteen of the more important crafts were organised into guilds (Sreni, Puga), each of which was presided over by a Pramukha (foreman), Jyeshthaka (elder) or Sresthin (chief). Sarathavaha was the caravan-leader. A Pali text refers to sea-voyages and of trading journeys to the coast of Burma, the Malay world (Suvarna-bhumi), Ceylon (Tamraparni) and even to Babylon (Baveru).
The principal sea-ports were Bharukachcha (Broach) Suparaka (Sopara, north of Bombay) and Tamralipti (Tamluk in West Bengal). Of the riparian ports, Sahajati (in Central India), Kausambi on the Yamuna, Banaras, Champa and later Pataliputra on the Ganges and Pattala on the Indus, deserve special mention.
The great inland routes mostly radiated from Banaras and Sravsti. The chief articles of trade were silk, embroidery, ivory, jewellery and gold. The system of barter was also prevalent. This led to localisation of crafts and industries and the emerging of artisans and merchants as important social groups. Besides others, these cities began to use coins made of metals for the first time.
The earliest coins belong to the fifth century B.C. and they are called punch-marked coins. The standard unit of value was the copper Karshapana weighing a little more than 146 grains. Silver coins were also in circulation.
The rural economy was mainly agriculture based. Rice was the staple cereal produced in eastern U.P and Bihar in this period. It was an economy which provided subsistence not only to direct producers but also to many others who were non-agriculturists. The greater part of the land came to be owned by gahapathis (peasant-proprietors).