It looks rather like it may be neodymium(Alexandrite) glass. If you hold it near a flourescent tube does it raemain pale amethyst of turn to pale blue or pale green - if so it is neodymium glass. As far as I am aware WF did not do Neodymium objects. It would then probably be Czeck or Murano. Also from a rusty memory I feel that vases of this shape were always coated with an thick, clear, outer layer.