I think, playing card are not characters (for use in plain text). Usually, one says (in german) Herz-A, Herz-K, Herz-10 or one uses the suit characters already in UNicode <heartsuit>10 etc.
Only the french suits are currently in, one can consider encoding the suits of Mahjongg, german, swiss, italian and spanish card, too. And the special sign printed on Joker cards (a five pointed star in a circle) But not more. For information on card games and cards, you may want to consult http://www.pagat.com or Detlef Hoffamnn: Kultur- und Kunstgeschichte der Spielkarte, Jonas-Verlag, Marburg, 1995. --J"org Knappen
