Sue, JP thanks so much
So... gathering everything together where I am at the moment is:
Not any Ysart
Not Whitefriars (but I love their cloudy white lattice - gorgeous)
And my feelings are it isn't Studio glass or more contemporary glass:
a) the foot, the finish on the foot,
b) the use of a mould (I think) to make the combing
c) the lamp glows bright orange under blacklight I found just now- manganese content?
d) yes now looking again in the light, it is full of tiny bubbles and some little black flecks including one larger one embedded in the glass.
I feel it is older than 80's or at least it feels 50's ish to me. But how does that metal fitment fit in with that?
I don't think it's Italian because of the finish on the base of the foot - wouldn't that be polished flat if it were Italian
I'll keep looking
(and if anyone knows where that red lattice Vasart is for sale, please let me know)