It will get shifted after it has been identified and we know it belongs there.

Your photos make me wonder if the colour of the glass has been achieved using a spray coating? It looks as if it would scratch off, but it might just be the way the photo has come out. (and my ageing eyes)
I don't think it has anything to do with Clutha. I do know what that looks like and it's very finely blown and often a bit "wonky". It does not come in all one colour, it's all streaky. I'm sure it's much more recent than that.
