but in a few cases the value of metals in fiat moneys have been allowed to rise to values larger than the face value of the coin. In India, for example fiat Rupees disappeared from the market after 2007 when their content of stainless steel became larger than the fiat or face value of the coins. In the US, the metal in pennies (97.5% zinc since 1982, 95% copper in 1982 and before) and nickels (75% copper, 25% nickel) has a value close to, and sometimes exceeding, the fiat face value of the coin. History Commodities often come into being in situations where other forms of money are not available or not trusted, and these are social norms. Various commodities were used in pre-Revolutionary America including wampum (shell beads), maize (corn), iron nails, beaver pelts, and tobacco. In Canada, where the Hudson's Bay Company and other fur trading companies controlled most of the country, fur traders quickly realized that gold and silver were of no interest to the First Nations. They wanted goods such as metal knives and axes. Rather than use a barter system, the fur traders established the made beaver (representing a single beaver pelt) as the standard currency, and created a price list for goods: 5 pounds of sugar cost 1 beaver pelt 2 scissors cost 1 beaver pelt 20 fish hooks cost 1 beaver pelt 1 pair of shoes cost 1 beaver pelt 1 gun cost 12 beaver pelts Other animal furs were convertible into beaver pelts at a standard rate as well, so this created a viable currency in an economy where precious metals were not valued. However, for convenience, Hudson's Bay post managers exchanged made beaver coins, which were stamped pieces of copper or brass. Long after gold coins became rare in commerce, the Fort Knox gold repository of the United States functioned as a theoretical backing for Federal Reserve. Between 1933 and 1970 (when the U.S. officially left the gold standard), one U.S. dollar was technically worth exactly 1/35 of a troy ounce (889 mg) of gold. However, actual trade in gold bullion as a precious metal within the United States was banned after 1933, with the explicit purpose of preventing the "hoarding" of private gold during an economic depression period in which maximal circulation of money was desired by government policy. This was a fairly typical transition from commodity to representative to