Mule coins were deliberately produced by US Mint employees for sale to coin collectors in the mid-1800s.[3] However, no authentic (accidental) mules of United States currency were known to exist. This changed in the 1990s, when a Lincoln cent (dated 1993-D) with the reverse of a Roosevelt dime were discovered.[note 1][5] In 2000, Frank Wallis of Arkansas discovered a Sacagawea dollar with the obverse of a Washington quarter.[6]
List of known coins
As of September 2019, 19 examples have been confirmed, 16 of which are owned by a coin collector named Tommy Bolack.[7][8] Three different die pairs have been identified among the examples.[7]
Coin
Die pair
Discovered
Notes
1
#1
May 2000
The "Discovery" specimen, owned by Tommy Bolack. Graded MS-66 by the PCGS.