Square appeal. Le Vian's necklace and pendant, set in 14k rose gold, light up the night with diamonds (5/8 ct. t.w.) in stunning fashion. Approximate length: 18 inches. Approximate drop: 1 inch. 5/8 Carat Diamond Necklace. Diamond Color Rating Code: H-I. Diamond Clarity Rating Code: SI2-SI3. Diamond Cut: Round. Almost all gemstones and blue and black diamonds have been treated to enhance their beauty and require special care. All gemstone carat weights (ct. t.w.), if mentioned, are approximate; variance may be .05 carat.