0.8 Carat Purple Lab Alexandrite Ring, Hexagon Cut Lab Alexandrite Ring Platinum. The main gemstone changes colors and is lab created, measuring 6mm x 6mm. This item is 925 sterling silver and available in two color options: Rose Gold or Platinum Plated (Silver). Available in full and half sizes from 4.5 -12. 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.