Commodity market in Sumer between 4500 BC and 4000 BC. Sumerians first used clay tokens sealed in a clay vessel, then clay writing tablets to represent the amount—for example, the number of goats, to be delivered. These promises of time and date of delivery resemble futures contract. Early civilizations variously used pigs, rare seashells, or other items as commodity money. Since that time traders have sought ways to simplify and standardize trade contracts. Gold and silver markets evolved in classical civilizations. At first the precious metals were valued for their beauty and intrinsic worth and were associated with royalty. In time, they
Commodity degrees, these economists turned to supply and demand to establish the price of commodities. Marx held that the "price" and the "value" of a commodity were not synonymous. Price of any commodity would vary according to the imbalance of supply to demand at any one period of time. The "value" of the same commodity would be consistent and would reflect the amount of labour value used to produce that commodity. Prior to Marx, economists noted that the problem with using the "quantity of labour" to establish the value of commodities was that the time spent by an unskilled worker would