Analysis of information sources in references of the Wikipedia article "Coin collecting" in English language version.
His goal was to assemble a complete collection of United States regular issue coins, of every date, metal, denomination, and mint mark known to collectors at the time. He accomplished this monumental feat by 1950, by purchasing the last gold coin he needed (1841 $2 1/2) in 1949 and the last silver coin he needed (1873-CC no arrows dime) in 1950.