This pattern is rarely found in such astonishingly pristine condition. The bright enamels are all intact. There are no chips, no cracks, no crazing and no repairs. It rings nicely when tapped.
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.
The Mason's Collectors' Club code for this pattern is: OA1.
Note: I have a second matching plate for sale here in my Ruby Lane shop which has one slight flaw.
I guarantee the authenticity of all items I sell, and disclose any damage or restoration. Your satisfaction is guaranteed, or your money back! PayPal accepted. Visa/MasterCard/American Express/Discover accepted.
Early Mason's Ironstone Plate "Mogul", Antique c 1815