Created by Bulgari, Rome, this contemporary black onyx and diamond "Mamba Nero" necklace is set in 18K gold. It is designed as an ultra-flexible onyx snake with marquise-cut diamond eyes clasping its tail in its mouth, with sugarloaf cabochon onyx clasp. Sleek, unusual and beautifully hand-engineered, this Bulgari "Black Mamba' necklace is the most rare and ultra-dramatic version of this iconic jewel.