In view of handle I'd suggest technically not a decanter (although you can get decanters with handles) - there doesn't appear to be any evidence of abrasion that occurs within the neck where a stopper would sit, so most likely a water jug or wine carafe. I think this style of crest is called 'demi-rampant' - this one looks a little like a griffin, possibly? - something similar, but with lions, forms the mark for Greener and Davidson pressed glass. This one is wheel engraved and looks as though it's rising from a coronet maybe - looks good quality, and quite adequate for nobility
I'm not sure about who is entitled to wear what - is it a Baronet that may wear a coronet?
It may well be c. 1880 - difficult to say looking only at the screen - you don't give any indication of wear, which of often a good indicator.
Either side of the main frosted band, and the central crest, there is a continuous chain of wheel engraved small ovals - a style of decoration which goes back to the late C18, but am sure was also used during the Regency and early Victorian periods - so much was copied - and the handle looks more late Victorian than earlier. No motto either, so no help there, but would look good on the table and might impress guests