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
Simple commodity production persists within industrialised capitalist economies in the form of self-employment by free producers. Capitalist firms sometimes contract out specialised services to self-employed producers, who can produce them at a lower cost, or provide a superior product. In Marxian political economy, simple commodity production also refers to a hypothetical economy used to interpret some of Karl Marx's insights about the economic laws governing the development of commodity trade: it refers to a market economy in which all producers own the resources (including the ability to work) that they use in production. No-one is a proletarian, selling his or her labor power