A platter of the same design and with the same mark is in the collection of the Victoria & Albert Museum in London. This example is 9" diameter and in excellent condition. The following information is from the web page "A-Z of Stoke-on-Trent Potters."
Ralph Wedgwood (& Co)
Ralph Wedgwood was the eldest son of Thomas Wedgwood (cousin & partner of Josiah Wedgwood) he carried on business as a potter under the style Wedgwood & Co at the Hill Works, Burslem.
He was in partnership with Tomlinson & Co at the Ferrybridge Pottery (Yorkshire), this partnership was not of long duration. His partners being dissatisfied at the large amount of breakage caused by his experiments and peculiar mode of firing, the partnership was dissolved and he retired from the concern, having succeeded in getting a thousand pounds awarded to him as his share of the business. After the dissolution, which took place in or about 1800 or 1801, the style of Tomlinson & Co. was resumed.....
At the Ferrybridge works Cameos, medallions and other ornamental articles, in the time of Ralph Wedgwood's connection with the works, were made in imitation of those of Josiah Wedgwood - to which they were, however, very inferior both in body and finish.
SOURCE: Jewitt's "Ceramic Art of Great Britain 1800-1900"