2.18 Marquise Cut Sapphire w/ Diamonds in 14k White Gold.  This incredible engagement ring is finished in 14 karat white gold and features a 2.18 carat marquise cut sapphire. The marquise cut is rather thick and the saturation of the cobalt blue is divine. Held with prongs on the points, and shared prongs with the small diamond accents give this ring a clean and minimalist appearance. The beauty of the sapphire is highlighted in this gorgeous modern mounting.