Golden” South Sea cultured pearls have become increasingly popular. Although distinguishing natural- from treated-color yellow pearls is fairly straightforward when they have been treated with inorganic chemicals or dyes after drilling, this separation is more difficult when the pearls have been heat treated prior to drilling. Shane Elen addresses this difficulty in his article on South Sea “golden” pearls, and suggests that UV-Vis reflectance spectroscopy can be used in conjunction with other detection methods to identify pearls that have been heat treated to attain their yellow color. This necklace is composed of 29 natural-color cultured pearls that range from 13.0 to 17.3 mm. Each of the natural-color cultured pearls in the earrings measures 13 × 14 mm. Courtesy of Tara & Sons, New York. Photo © Harold & Erica Van Pelt––Photographers, Los Angeles, California.