Thanks for the comments on the glass - it sounds like it might be a lead glass, but of relatively low lead content.
I have been looking at some of my 'oddities', and I have a paperweight with very similar cane structures (and some of the colours), which belongs to the unknown group of antique European paperweights that I refer to as 'starfish' paperweights. I call them that because many have unusual canes with 5 short straight arms to them. I am working on an article on these, but will try and post some images of the paperweight I have in mind and the relevant canes in the next day or so.
They are a diverse groups of designs - concentrics, colour grounds, harlequins, scrambles. They probably date to the late 19th century, and may well be Belgian but not Val St Lambert. More anon.