Ellis Stanyon's “Florin vs. Penny” in the March 1899 issue of Mahatma, Vol. 2, No. 9, p. 210, is an early example of the effect of turning a silver coin to a copper one, then back and forth several times.

In 1914, Camille Gaultier defined the basis for what would come to be called the Spellbound effect in his Prestidigitation Sans Appariel. Jean Hugard, in his translation of Gaultier's work, Magic Without Apparatus, 1945, p. 292, gives the passage as:

“All of these procedures can be used, also, to produce an open (instead of a secret) change of coins, in full view of the spectators. For example, a silver five-franc piece can be transformed into a hundred-franc gold coin, a large bronze sou into a two-franc silver coin, or a penny into a florin. In making such changes, the sleights should be combined with one another, so that the same change is not used to restore the transformed coin to its original value. That is to say, the methods employed should be varied, in order to avoid unwise repetition.”

Next came Edward Victor's “The Changing Coin” in Magic of the Hands (1937, p. 42), followed by Dai Vernon's “Spellbound” routine in Stars of Magic, 1946, p. 31.