For thousands of years, turquoise has been used in jewelry and other items of adornment. In recent times, much of this material has been treated to improve its appearance and wearability. In particular, a relatively new, proprietary treatment has been used to enhance millions of carats of turquoise. Referred to here as the "Zachary treatment," it cannot be detected by standard gemological techniques. The lead article in this issue describes the properties of this treated turquoise, and discusses methods to identify it. All of the turquoise shown here, which is from the Sleeping Beauty mine in Arizona, has been treated by this method. The necklace is composed of 12.5 mm turquoise beads separated by diamond rondelles, with a white gold clasp containing 1.65 ct of diamonds. The carving measures 30 × 60 mm. Courtesy of Roben Hagobian, Glendale, California. Photo © Harold & Erica Van Pelt--Photographers, Los Angeles, California.