fiat money, with people trading in other goods being forced to trade in gold, then to receive paper money that purported to be as good as gold, and finally a fiat currency backed by government authority and social perceptions of value. Cigarettes and gasoline were used as a form of commodity money in some parts of Europe, including Germany, France and Belgium, in the immediate aftermath of World War II. They have continued to be used as currency in war-torn locations experiencing inadequate supply of common goods and monetary collapse, such as during the Siege of Sarajevo in 1993 or in Russian-occupied Kherson in 2022. Functions Although grains such as barley have been used historically in relations of trade and barter (Mesopotamia circa 3000 BC), they can be inconvenient as a medium of exchange or a standard of deferred payment due to transport and storage concerns and eventual spoilage. Gold or other metals are sometimes used in a price system as a durable, easily warehoused store of value (demurrage). The use of barter-like methods using commodity money may date back to at least 100,000 years ago. Trading in red ochre is attested in Swaziland, shell jewellery in the form of strung beads also dates back to this period, and had the basic attributes needed of commodity money. To organize production and to distribute goods and services among their populations, before market economies existed, people relied on tradition, top-down command, or community cooperation. Relations of reciprocity, and/or redistribution, substituted for market exchange. The city-states of Sumer developed a trade and market economy based originally on the commodity money of the Shekel, which was a certain weight measure of barley, while the Babylonians and their city-state neighbors later developed the earliest system of economics using a metric of various commodities, that was fixed in a legal code. Several centuries after the invention of cuneiform script, the use of writing expanded beyond debt/payment certificates and inventory lists to codified amounts of commodity money being used in contract law, such as buying property and paying legal fines. Legal tender issues Today, the face value of specie and base-metal coins is set by government fiat, and it is only this value which must be legally accepted as payment for debt, in the jurisdiction of the government which declares the coin to be legal tender. The value of the precious metal in the coin may give