 Numerous Indus Valley seals have turned up at Ur and other Mesopotamian sites, far outnumbering even local seals which shows their preference for the Indian economic currencies and seals.The "Persian Gulf" types of circular, stamped (rather than rolled) seals known from Dilmun, that appear at Lothal in Gujarat, India, and Failaka, as well as in Mesopotamia, are convincing corroboration of the long-distance sea trade.What the commerce consisted of is less known