Deep purple vase with opal rim and foot.

I acquired this vase many years ago. It is a deep purple (not black amethyst) vase with an applied white opal rim and base. Although it photographs as blue, I can assure you it is purple. It is 10" tall and 8" wide. No makers mark. Any ideas as to the maker? It kind of looks like a Steuben shape, but none of the Steuben books indicate that they made any amethyst or purple with opalescent. Dugan? New Martinsville? Any suggestions or directives to references would be appreciated. Thank you.