This pattern is rarely found in such astonishingly pristine condition in a plate. The bright enamels are all intact. There are no chips, no cracks, no crazing and no repairs. It rings nicely when tapped. There is a small nick on the foot rim (shown in the last photo).
The large (9-1/2") plate is marked in blue on the back: PATENT IRONSTONE CHINA within a banner with a crown above. On page 46 of Godden's "Mason's Patent Ironstone China: The Illustrated Guide", 1971, he dates this mark 1813-1815.
I have a second, matching plate available for sale here in my shop.
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