Chaumet Necklaces. SKU: 083166-000. Metal Type: White Gold. Metal Stamp: 18k. Gem stone type: Diamond. Stone weight: 5.34ct. Chaumet Josephine Aigrette Imperiale 18k White Gold 5.34ct Diamond Necklace. This necklace in 18k white gold features a pendant paved with 90 brilliant-cut G VS+ diamonds totaling 5.34 carats, with adjustable lengths of 39, 42, and 45 cm.