Made 1849, by Carl Otto Zetterberg in Stockholm, Sweden. A so-called memorial ring or locket ring (poison ring) 18k gold, engraved and enamel decoration, hidden compartment with hinges still containing a lock of hair. Rings like this have been used throughout history to carry perfume, locks of hair, devotional relics, messages and other keepsakes, so they have also been known by other names. Super romantic.
ring size between 8 and 8.5 / or 18 – 18.5mm inside diameter.