This Royal Chelsea cup and saucer is marked as pattern 190A. It is a copy of a cup and saucer from a tea set made about 1784 for the Duchess of Devonshire. The inside of the cup is white except for a narrow gold band. The saucer and the outside of the cup are decorated with flowers and a rayed design of gold lines which were applied free-hand. There is a flower design in the center of the saucer.
Royal Chelsea was produced by New Chelsea China Co Ltd Longton-Staffordshire Potteries from about 1943 to 1961. This is a lovely piece!