Lab Created Alexandrite Jewelry Set, Color Changing Alexandrite Hexagon Cut. The main gemstones on this set measure 6mm x 6mm. This jewelry set includes a necklace with pendant (length: 45cm), one ring (available in sized 4.5- 12), and one pair of stud earrings. This item is 925 sterling silver and available in either rose gold color, or platinum plated (silver). This item includes a velvet gift box and a certificate of authenticity with purchase. This item is made to order, please allow about 10-15 days for processing and delivery of this item.