Sterling Silver Solitaire Round Cubic Zirconia with Extendable Necklace. Sterling Silver Diamond-Cut Cable Chain with Round Solitaire Cubic Zirconia. Length of Necklace can be adjusted to be in three different lengths: 20", 19"1/4 or 18"1/2 Carat weight of Round Cubic Zirconia is 1.40 Carat. Solitaire Cubic Zirconia is 6.0mm in Diameter. Elegant Gift box is included.