Add Yahoo as a preferred source to see more of our stories on Google. When you buy through links on our articles, Future and its syndication partners may earn a commission. An amethyst set in silver ...

A rare ring, set with sapphire, emerald and garnets and once owned by a medieval bishop, is coming to auction on March 26 sale of jewelry, silver, and objets d’art at Noonans Mayfair, in London.