Double Eagle

A double eagle is a gold coin of the United States with a denomination of $20. (Its gold content of 0.9675 troy oz (30.0926 grams) was worth $20 at the 1849 official price of $20.67/oz.) The coins are made from a 90% gold (0.900 fine = 21.6 kt) and 10% copper alloy and have a total weight of 1.0750 troy ounces (33.4362 grams).

The "eagle", "half eagle", and "quarter eagle" were specifically given these names in the Act of Congress that originally authorized them ("An act establishing a mint, and regulating coins of the United States", section 9, April 2, 1792). Likewise, the double eagle was specifically created as such by name ("An act to authorize the coinage of gold dollars and double eagles", title and section 1, March 3, 1849).

The first double eagle was minted in 1849, coinciding with the California Gold Rush. In that year, the mint produced two pieces in proof. The first resides in the Smithsonian Institution in Washington, D.C. The second was presented to Treasury Secretary William M. Meredith and was later sold as part of his estate—the present location of this coin remains unknown.

In 1850, regular production began and continued until 1933 (when the official price of gold was changed to $35/oz by the Gold Reserve Act). Prior to 1850, eagles with a denomination of $10 were the largest denomination of US coin. The $10 eagles were produced beginning in 1795, just two years after the first U.S. mint opened. Since the $20 gold piece had twice the value of the eagle, these coins were designated "double eagles".

Regular issue double eagles come in two major types and six minor varieties as follows:

Due to the less desirable artwork and therefore lower demand, liberty coronet $20 gold pieces are less often encountered, and the common subtype commands less than the St.-Gaudens' type. In 1866, the motto "In God We Trust" was added to the liberty coronet double eagle, creating a second subtype. In 1877, the coin's denomination design on the reverse was changed from "twenty D" to "twenty dollars" creating a third and final subtype for the series. An 1879 pattern coin was made for the quintuple stella using a design combining features of the liberty head double eagle and stella pattern coin and using the same alloy as the stella (90 parts gold, three parts silver, and seven parts copper). However this coin was stolen in July 2008.

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