Explanation:

Kalibangan in Rajasthan has given the proof of the earliest (c. 2800 BC) ploughed agricultural field ever revealed through a quarry. Similar ploughing is used for two simultaneous crops in this area even today. The unique mark of this early phase is pottery, characterized by six fabrics labelled A, B, C, D, E and F, which were later identified also at Sothi in North Western India. Small blades of chalcedony and agate, shell, carnelian, terracotta and copper, bangles of copper, terracotta objects like a toy-cart, wheel and a broken bull, a bone point etc. have been found here.