Commodity money as a theoretical backing for federally issued "gold certificates" to substitute for the gold. 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 influential economists. This was a fairly typical transition from commodity to representative to fiat money,
United States Commodity Funds United States Commodity Funds United States Commodity Funds LLC (USCF) is a US company based in Oakland, CA, specializing in managing exchange-traded commodity funds, which are often referred to as commodity-based exchange-traded funds (ETFs). USCF was one of the earliest issuers of exchange-traded commodity funds in the United States. It is best known for launching in 2006 the first crude oil based exchange traded commodity fund in the United States, United States Oil Fund, LP (ticker: USO), as well as launching in 2007 the first natural gas exchange traded commodity fund, United States Natural Gas Fund, LP (ticker: UNG). USO