There are a number of small and fine shelf wear marks to the base so I know it's got some age but I don't know how much age
Yes sorry I meant to say fingernails were what I used, I must try to be more specific

I'd be mortified if anyone went near any of my glass with a metal nail

From what I have seen on internet searches, the engravers that you have suggested worked in Stourbridge/Dudley area for Webb and Stuart glass if the info is right? I only live about 25 miles from Stourbridge and in fairness, theres a lot of glass from that area regularly found in charity shops and antique/collectors fairs and similar around here but not usually so ornate so the geography may be a hinter too?

This gives me names and eras to research, thanks again Chriss