Featuring 17 lab-grown white sapphires set in a graduating shape, the Large Curve Necklace combines the wearability of a delicate chain necklace with striking sparkle. The Fine Print: Metal: 18k gold vermeil - a 2.5 micron layer of gold over sterling silver. Setting: 3-prong Stone Type: Lab-grown white sapphire Stone Shape: Round cut Closure: Spring ring Lab-Grown Sapphire Carat: 1.9 CTW DEW What is Lab-Grown?