Striking French Art Deco 18K, Platinum, Diamond and Black Onyx ring. The ring is very well crafted. The center Old European cut diamond is .55 carat with SI2 clarity and H-I color. The diamond looks larger and is quite stunning against the black onyx. There are six rose cut diamonds on each side (12 total) with a total weight of .24 carat. The back side of the setting is finely pierced and crafted making it almost as beautiful as the front. Size 7 1/4. The workmanship is fine and the condition is excellent. Circa 1920. The onyx portion of the ring measures approximately 15.7mm long and 10.7mm wide.