Dish on legs, JW mark - Joyce Withey

Hello everyone,  Can anyone help me out with this odd dish that I picked up the other day?  It is a pottery dish on tall spindly legs.  The inside of the dish is glazed green, whilst the outer and the legs are unglazed and a mottled brown colour.  Marked on the base with a monogram that could be JW, but I can't find it in any of my books or online.  Anyone got any ideas?
Cheers in advance!
Ceri

I don't recognise the mark but your dish very much reminds me of a half avocado (hass) and wondered whether it was made for serving guacamole? just a thought.

Now there's a thought! Maybe I should put this thing to good use

I also meant to add that there may be a connection to Mexican pottery due to shape/colour : )