Born in Bloomington, Indiana. Attended Fresno State College. Married to Ruth with two sons. Moved to California in 1919. Played football with San Joaquin Valley American Legion professional team. Employed with Tidewater Oil Company after 1929. He retired in September 1968.

Mitchell began collecting coins at age 12. He was a founding member of the California State Numismatic Association in 1947 and the California Exonumist Society in 1960. He served as president of CSNA for 1949-51. He served as second vice president of the ANA 1943 to 1947. He received the ANA Medal of Merit in 1964. He served as president of TAMS 1968 to 1970. He appeared on a medal issued by the CSNA to honor his presidency 1949-1950. He was honored by TAMS with a medal struck by Medallic Art Company.

He was named a Numismatic News Numismatic Ambassador in 1979. In 2016 he was inducted into the ANA Hall of Fame.

Author with Russell Rulau of Embossed Shell Store Cards. Author with Charles Kappen of Depression Scrip of the United States Period of the 1930's in 1961. Author with Neil Shafer of Standard Catalog of Depression Scrip of the United States published in 1984. He was west coast representative for the Franklin Mint 1969 to 1977.

Mitchell was noted for his bald head and was frequently referred to as "Curley." He was also described as one of the shining personalities in numismatics. He died in Fullerton, California.

Coins from the Mitchell collection were consigned to a Kreisberg & Cohen sale October 4, 1979, and an S. C. Coin & Stamp Co. auction December 1, 1980.

profile: TAMS Journal VI/4 Aug/Oct 1966 p. 104 (photo)

obit: CW 12/25/91; NN 12/31/91; NUM 105 Feb 1992 page 261