Carse Antiques has dated this piece to the 1900s.
Lord Roseberry, after whom this shape was named after was British Prime Minister between 1894 / 5 and was a Liberal. His estate was on the other side of the Forth from the Fife pottery Kirkcaldy.

The piece is not marked but this is not unusual for the earliest and thus rarest pieces of Wemyss. There are a couple of very minor hairline cracks near the top but otherwise this is in very good condition.
RARE.
SIZE; 16 1/2" tall
Carse Antiques has dated this piece to the 1900s.
You can view the stock and full dealer information on the Carse Antiques Profile Page
Carse Antiques is a registered member of LAPADA