Thank you Nev, yes it is a Sowerby plate in a colour commonly known as Rubine. As Nev says, there may be a Sowerby mark on the back, although not all were marked.
The plate and stand shown on my site are separate items, the plate is sitting on the stand. This design was made from the late 1870's until possibly the 1930's in a number of colours including carnival. I don't think this pattern ever appeared in any of the known pattern books. The only other Sowerby glass I have seen in this colour dates from around 1910 so maybe this plate was made around this time.
Mike