Vintage Anton Michelsen Sterling Silver Porcelain Box Ring 1970s

A vintage Anton Michelsen solid silver and porcelain ring consisting of a silver ball set in a white porcelain box and mounted above a square profile U shaped shank - marked for Sterling silver and for Anton Michelsen, jewellers to the Royal Court of Denmark - total weight 12.4grms - dimensions of face 18 x 18mm - current ring size approx N AU/UK (6.5 US) - c.1970 Denmark