I have had this vase for a few months now and so far it has defied identification. I thought maybe a bit of Stevens & Williams Caerleon but the shape seems too controlled (if that makes any sense), likewise I don't think it is by WMF or Loetz. All I have seemed to have accomplished is to rule out various manufacturers.
On the whole quality feels pretty good, the vase is around 8" tall - about 20cm (I don't have the vase with me so will need to check that), the iridescence has distinct 'bands' which I have tried to capture in the fourth photo.
The rings toward the base remind me of Stuarts Stratford Rings but all the other examples I could find taper in some way and none were either bubbly or iridescent.
All thoughts would be most welcome!
John