Art Deco brooch 18K gold set with calibré cut onyx surrounding an old cut diamond (approx. 2.4 cts), length 7cm

Art Deco brooch 18K gold set with calibré cut onyx surrounding an old cut diamond (approx. 2.4 cts), length 7cm

Mounting: Good overall condition. Shows signs of wear with some minor scarcthes.
18K mark on the clasp

Gemstones: Good to very good overall condition. A small chip on the culet.
Approximate measurements of the diamond (bezel set): 8.60x8.11x5.62 mm Weight: approx. 2.4 carats
VS/I-J
Fluo: none