The U.S. Assay Office contract was taken over by a new private firm that was called the United States Assay Office of Gold. This semi-official Mint produced eagles, double eagles and $50 ingots until December 1853, at which time its facilities were closed for reorganization as the official San Francisco Mint. Because the new official Mint could not at first produce coins as fast as the old semi-official one, several private companies opened to compete with the new federal Mint through 1854 and 1855.
In addition to the shortage of large denomination coins there was always a shortage of small change for use in retail stores. Several small, anonymous companies therefore produced gold dollars, half dollars and even quarter dollars using a number of different designs. These fractional coins were struck from 1852 to 1882; it has been suggested that the later strikes were never intended for circulation but were merely souvenirs of California. Federal law in 1864 had forbid private coinage of any sort and some manufacturers of these pieces were prosecuted for counterfeiting after the 1864 law went into effect.
A number of eagles and half eagles were struck in Oregon in 1849, despite the objections of the new territorial governor. Presumably his orders eventually prevailed, as the issue was not repeated.
The Mormon government issued $2.50, $5, $10 and $20 coins in 1849, as well as half eagles in 1850 and 1860. This last issue was made of Colorado gold from the Pikes Peak area. Most of the early issues of Mormon gold did not receive widespread acceptance, as they were underweight by as much as 15 percent.
The last period of “legal” pioneer gold coins (i.e., issued before 1864), was the Pikes Peak gold rush of 1860 to 1861. Only three major firms produced coins in these two years, although several unverified patterns are known. It is interesting to note that in 1862 the largest of these companies, Clark, Gruber and Co., sold its equipment to the government, which intended to open a Branch Mint in Denver. The specie hoarding of the Civil War presumably doomed this project, and a Denver Mint did not open until 1906.
Other pioneer gold issues are known for Alaska and the northwestern states, but they were primarily made as souvenirs and did not circulate as coinage.
Just like regular coins, pioneer gold coins were subject to Gresham’s Law. Those that were of full weight and value or better were hoarded and probably melted, while those that were undervalued were spent as soon as possible to avoid getting stuck with the coin.