This special issue is devoted to the geographic origin of specific colored stones. On the front cover, clockwise from left: a 64.45 mm Sri Lankan sapphire crystal, a 24.34 ct Sri Lankan blue sapphire, two cuprian tourmalines from Mozambique (55.52 and 45.74 ct), a 16.65 mm pink-purple Sri Lankan sapphire crystal, a 10.90 ct Burmese ruby, and an 11.11 ct Sri Lankan alexandrite. Courtesy of B&B Fine Gems and Evan Caplan. The back cover shows emeralds from the Chivor mine in Colombia (3.90 ct faceted stone and 2.35 cm crystal), courtesy of William Larson, Pala International. Photos by Robert Weldon/GIA.