Amethyst-citrine quartz, known in the trade as ametrine, is one of the most enigmatic gem materials to appear on the market in recent years. Early reports suggested that it might actually be a synthetic, or the product of treatment. The lead article in the issue, by Drs. Vasconcelos, Wenk, and Rossman, takes the reader to the actual deposit in Bolivia where thousands of kilos of ametrine have been mined, shares the fashioning of these crystals, and discusses the cause of the unusual color zoning. Contemporary cutters and carvers have discovered the exciting possibilities that this material offers. The 78-ct ametrine illustrated here set in an 18k gold "collar" was fashioned by master German designer and gem carver Bernd Munsteiner, of Idar-Oberstein, the innovator in such "fantasy" carvings. The three loose ametrine carvings—142, 44, and 263 ct—are by renowned American lapidary artist Michael M. Dyber, Rumney, New Hampshire. Photo © Harold & Erica Van Pelt—Photographers, Los Angeles, CA.