Peak uranium gold, silver, copper or nickel, uranium is not widely traded on an organized commodity exchange such as the London Metal Exchange. It is traded on the NYMEX but on very low volume. Instead, it is traded in most cases through contracts negotiated directly between a buyer and a seller. The structure of uranium supply contracts varies widely. The prices are either fixed or base on referenced to economic indices such as GDP, inflation or currency exchange. Contracts traditionally are based on the uranium spot price and rules by which the price can escalate. Delivery quantities, schedules, and prices vary from
Commodity money cans or foil pouches of mackerel fish fillets, which have a fairly standard cost and are easy to store. These may be exchanged for many services in prisons where personal possession of currency is prohibited. In situations where the commodity is metal, typically gold or silver, a government mint will often coin money by placing a mark on the metal that serves as a guarantee of the weight and purity of the metal. In doing so, the government will often impose a fee which is known as seigniorage. The role of a mint and of coin differs between commodity money