I posted this on www.whitefriars.com
as I thought it looked similar to some early Powell pieces, opinions so far there are maybe, maybe not, maybe Leerdam (hope that's a fair summary) Here's the link...http://www.whitefriars.com/isit_contents.php?ID=5195
It's 16.5cm (6 1/2in) diameter, 7cm (2 3/4in) high, plenty of base wear and clean concave polished pontil.
Appologies for the colour of the pics, my camera is refusing to take a good shot so I've colour balanced them to look as close as I can. I would describe the colour as a soft jade, that looks like green sheet glass in refraction (does that make sense?)
I think it's a nice quality simple bowl, that I'm guessing is pre 1940s and post 1860s?....does anyone recognise it?
Many thanks, Martyn.