Andy McConnell's book is an obvious choice with which to learn much about these things, since it concentrates on decanters, but I know it's pricey.
The other suggestion if you have queries and don't have immediate access to an appropriate book is to send couple of good pix to the glass department at the V. & A. in London .. ceramicsandglass@vam.ac.uk
They don't guarantee an answer, and sometimes might take a week to reply, but my experience of them has usually been good.
Pix of clear glass need to avoid fussy backgrounds of differing colours etc...... a plain uniformly dark background is best, with angled light, and possibly best lit from behind if you can.
Certainly the shoulder was fashionable in the period I suggested, as was that particular shaped cartouche, and the same may be said of the kick. The amount of wear looks to suggest substantial age, but as we know the Victorians copied just about everything, so difficult to be certain, although not sure that they copied these things.
Let's hope we get an expert to have a look.