This plate dates to the Qing dynasty, Qianlong period, c. 1752-54, and was made for the Swedish Councillor, Count Herman Tresmeden Cedercreutz (1684-1754)and his wife Maria Campbell (1721-65), who married in 1752.
Count Cedercreutz was awarded The Order of the Seraphim in 1748 - which is included in the coat-of-arms (bottom left) and was advanced to Count in 1751, which would give us a date for this plate in the period between his marriage in 1751 and his death in 1754.
The decoration is in Grisaille, sepia and gilt.
Some further reading: Wirgin, Jan, Från Kina till Europa, illustrated and described on p. 139.
Sincerely
Jan-Erik Nilsson