Here is a, large and elegant Sterling silver ring by the esteemed Danish silversmith Carl Ove Frydensberg, who worked in Copenhagen from 1949 to 82.  It features a large oval amethyst-coloured stone, 

Condition: Excellent, no visible damage

Marks: COF encircled with Sterling Denmark

Size: to fit finger size UK small P,  US 7.75, EU 56. Top of ring is 2.7 cm (1.1") long

Year: 1970s