Source : Webster's Revised Unabridged Dictionary (1913)

Alchemistic \Al`che*mis"tic\, Alchemistical \Al`che*mis"tic*al\,
   a.
   Relating to or practicing alchemy.

         Metaphysical and alchemistical legislators. --Burke.

Source : WordNet®

alchemistical
     adj : of or relating to alchemists [syn: {alchemistic}]