In Golden Age detective fiction few things are stolen so often as pearls, which are portable, valuable, difficult to identify and easy to sell or pawn. The theft of pearls is in fact so common as to be a cliché, to the point where a ‘string of pearls’ comes to stand for nothing more than a conventional clue which in itself means nothing and suggests nothing. And yet pearls do mean and suggest many things. Moonlike, mysterious, feminine (as underlined by the term mother of pearl), and born from the ocean like Venus, pearls have historically been objects of desire for many if not most women, but one of the questions implicitly raised in a number of works of Golden Age detective fiction is whether some women have more right to them than others. Sometimes a judgement about this may be made on purely aesthetic grounds, but usually the question is more value-laden, because pearls are both a reward for and a symbol of sexuality. A simple pearl necklace may be a suitable adornment for a virginal young girl but a profusion of pearls is a clear danger sign, and pearl necklaces can also draw unwelcome attention to the ageing necks of dowagers. In this sense, pearls are not objects of detection but subjects, hunting out and exposing who does deserve to wear them and who does not. Particular tensions attach to black pearls, partly because of their colour and partly because arguably the most famous black pearls on record were owned by Mary, Queen of Scots, a figure of considerable interest to Golden Age detective fiction. Other pearls may also have pasts which are both exotic and problematic, and pearls in general could suggest sorrow through a supposed connection with tears which led them to be considered unlucky for weddings; it was also often stressed that they could deteriorate and even ‘die’, investing them with a sense of organic life which enabled them to be troped as symbiotic with the women who wore them. While the theft of a pearl necklace kills neither the pearls nor their owner it shines a spotlight on the use of pearls to signal the social and sexual status of women and suggests that pearls’ vulnerability to theft implicitly comments on the potential of marriages to disintegrate or be disrupted by a rising divorce rate.