Marquise Cut Lab Created Alexandrite GemstoneThese loose marquise faceted cut lab created Alexandrite gemstones are available for a custom built ring by Nodeform Jewelry. Select your stone size & type, then select a ring setting that fits the shape and size of the selected stone. Add both to your cart and we'll create your ring! Lab Grown Alexandrite Specs: Sizes: 7 x 3. 5 mm 0. 6ct, 8 x 4 mm 0. 64ct, 9 x 4. 5 mm 0. 88ct, 10 x 5 mm 1. 2ct, 12 x 6 mm 1. 9ct, Treatment: Lab Created Blue green by