LATE ROMAN AMETHYST CAMEO DEPICTING CONSTANTINE THE GREAT IN GOLD RING Ca. AD 300 - 350 A late Roman large oval amethyst cameo depicting Constantine the Great, Emperor from 306 to 337 AD and the first Roman emperor to convert to Christianity. He is represented with short hair, a large nose and almond-shaped eyes. The cameo is set in a possibly later 18ct gold ring. Size: D:16.31mm / US: 5 3/4 / UK: L; Weight: 5.86g Provenance: Property of a London Ancient art collector, formerly in a Mayfair private collection of Mr. P. S., formerly acquired on the UK art market since the 1970s. This item has been cleared against the Art Loss Register database and comes with a confirmation letter. This piece comes with an authentication report by Sami Fortune, ancient jewellery specialist.