By Irene Neuwirth, these cabochon tanzanite stones are in 18 karat rose gold, in a scalloped and notched, tiny milgrain edged setting. The stones have beautiful and interesting variegation. The designer's secret for making sure this necklace lays perfectly? Look closely and you will see that each stone is mounted slightly higher than the center, so that when you put it on, it will not flip. Simply brilliant. The stones have a diameter of 1/2-in. and the chain measures 34-in. long.