An Art Deco style onyx and diamond necklace, consisting of a millgrained floral motif applied on a dog tag shaped concave onyx plaque, centrally set with an old-European cut diamond and further embellished with rose cut diamond accents, swinging from a scrolled surmount, to later added fine curb link chains and completed with a spring-ring clasp, London import marks stamped as '375', necklace drop length measures 22.5 cm, pendant length 2.5 cm, total weight of item 5.5 grams.