 Copper ingots from Oman and bitumen which occurred naturally in Mesopotamia may have been exchanged for cotton textiles and domestic fowl, major products of the Indus region that are not native to Mesopotamia.Instances of all of these trade goods have been found.The importance of this trade is shown by the fact that the weights and measures used at Dilmun were in fact identical to those used by the Indus, and were not those used in Southern Mesopotamia.