55693 is one of those numbers you get to know, like 100004, and I was puzzled because I remembered it as S&W's Jewelled
glass, and there isn't any on your example! So I looked it up.
There's a very similar piece to yours, slightly larger, which Gulliver p.119 gives as S&W's pattern number 14099, carrying the same registration mark. This example has two small Jewelled
posy vases incorporated.
Illustrations, including coloured examples, can be seen in Gulliver pp. 119, 166 and 266 (registered design drawing), and Hajdamach I pp. 278 and 280.