Source : Webster's Revised Unabridged Dictionary (1913)

Alquifou \Al"qui*fou\, n. [Equiv. to arquifoux, F. alquifoux,
   Sp. alquif['o]l, fr. the same Arabic word as alcohol. See
   {Alcohol}.]
   A lead ore found in Cornwall, England, and used by potters to
   give a green glaze to their wares; potter's ore.