Old Sheffield Plate? But how old?

I have this coffee pot but I am in discussion with someone as to it’s age and provenance. To me it looks Georgian but there are no marks except for what looks like a trident within a shield stamped on it’s bottom. The finial is unusual as it looks like a flower - could it be the white rose of Yorkshire?
It has an armorial, which is very rubbed but again I would think that denotes age.

I would be very grateful for any information at all. Thank you.