Making a playing card secretly magnetic by hiding a thin piece of steel between the layers of the card is described in the anonymous “MS III, 18”, also called the Asti Manuscript, c. 1670-1730 (see Gibecière, Vol. 8 No. 1, Winter 2013, p. 101). The prepared card was forced, then lost in the deck, after which a spectator used a wand to detect the card, finding that the card clung magically to the tip of the wand.