Craig I do not know if this is Harrach or not. I believe this type of opalescent pattern (although maybe not an exact match) is called Quadruple Diamond, but that may be a slang term. I have a large 11" Ewer with this type of pattern & it was attributed as English...I believe the Vaseline guide by Dave Peterson has this pattern in it, but cannot remember the attribution except I an fairly certain its not Harrach. Phoenix Art Glass in Phillipsburg PA made a very similiar pattern in a pitcher (pg. 71 in Leland Marple's Phoenix Art Glass guide) so I am of the opinion it could have been produced by several companies perhaps in both Europe & the U.S. Sorry not much help I'am afraid. Ken