The Grosvenor is a court band — rounded across the face and rounded again inside, so it sits close and turns easily — with a single round brilliant diamond set into the middle of it. The stone is rubbed over rather than clawed, its collar worked down level with the surface, so nothing stands proud to catch on a cuff or a glove. Everything either side of it is left plain and mirror polished, which is what makes the one stone read. Made to order, with the width, metal and finger size specified to your preference.