Paul, the label is from VSL but not normally not used on decorative glass but bricks. Valart is not a brand but it is a range or series of bricks with different patterns, produced by VSL.
It's been put on to fool people and sell better (I fell for it too) by somebody who had theses labels and our vases, i can't think of any other reason.
You can email VSL but I would be surprized if you'd get a reply due to the language barrier.
It's true, it doesn't look like anything from the Eldorado series, but as Herman had done some individual, unique pieces, I had hoped it could be one of them.
If you don't get a reply from VSL, I'll ask next time I'm over there.
Nice of mr Herman to reply so quickly.