David Pickett Antiques has dated this piece to the 18th Century.

The condition is very good overall with no dents or splits. Slight signs of copper bleed to the raised edges. The very solid cup body has a couple of scratches / hair line cracks but remains firm and intact. Small spots of solder strengtheners to the interior where it is attached to the base.
Weight approx 270g.
Height approx 14cm
Diameter of bowl approx 8cm.
Base diameter approx 7cm.
David Pickett Antiques has dated this piece to the 18th Century.
Specialists in old sheffield plate
You can view the stock and full dealer information on the David Pickett Antiques Profile Page