thanks Ivo - I had typed a reply to the other folk and you pipped me to the post - can you suggest an approximate date please.
What I was about to send was.................
quote................."and we have completely different tastes obviously as I think it's gorgeous" ......... sorry m, all I can see is a retro style i.e. something from the 1950's - although some of the others you mention have a distinct deco style, and that is something I go for in a big way - deco never seems quite to go out of fashion.
For me this has novelty interest only - it doesn't make me say 1920's ...... I'm trying to be more tolerant of other people's tastes - but is it my fault the world is full of philistines

But to be serious for a moment...........
What is obvious in this pot is the granular appearance within the glass (although the surface is smooth) - I haven't the time this evening to follow up your links, but will look later, but there is a similarity with some of the grainy/gritty textures on other pieces you've linked.
But quite probably Leerdam as Ivo now suggests. Sorry to hear Dirk is blaming us for his expanding collection - time perhaps for another hug for him

Christine - I'll consider parting with it, and let you know when I decide - meantime thanks for all the thoughts and suggestions.