Signet ring, with diamond

A lovely simple vintage ring, a 9ct white gold band simply set with a princess cut diamond. The shank is approx 4mm wide and 1.7mm thick. The Dimond is small, being approx 1.5×1.5mm, so about 10pts max. Probably a J/K colour and i1 clarity.
It has a total weight of 4.3g
UK Size K
Fully hallmarked Birmingham 2001
The ring has some marks and scratches on it, I think it looks worse in some of the images, but to the naked eye its very clean looking.