1 EPREUVES/PROOFS Oxford Journal of Archaeology, 33.2, 2014, 177-191 VÉRONIQUE DASEN HEALING IMAGES. GEMS AND MEDICINE Summary. The main purpose of magical gems was to secure divine protection, avert evil influences and heal various diseases. Some body parts are especially addressed, such as the stomach and the uterus. This concern seems to relate to ‘societal diseases’ also found in contemporary literature. How do these ‘healing pictures’ function? The analysis of the pictorial elements reveals different levels of therapeutic efficacy. Some images use visual plays upon words, others combine Egyptian and Graeco-Roman elements, allowing ‘bilingual’ readings. The mnemonic function of images, charakteres and voces magicae also requires further investigations. Objects could transmit the memory of oral rituals and knowledge. The transfer of magical figures on other media is very rare, but when it occurs, as on a few medical devices, it may help us to understand the mechanism of medico-magical performance, combining formalism and inventiveness. Most magical gemstones had a positive function: they secured divine protection, averted evil influences, and were used to repel or heal various diseases. In this paper, I would like to investigate further these healing qualities and the visual system constructed by the combination of pictures and signs (charakteres and logoi), a combination which we could designate by the term ‘glyph’, used by Severi (2004) in his studies on oral traditions to describe this kind of meaningful transformation of images into signs. More specifically, my paper focuses on two issues, the first of which concerns the logic guiding the engravers’ choices, with reference to medical and medico-magical literature. Why are some diseases explicitly shown and not others, though they are addressed in other media, such as the magical papyri or phylacteries? In addition, how do these ‘healing images’ function? Does the symbolic efficacy of the gems relate to the logic of medical magic, as expressed, for example, in the recipes collected by Pliny the Elder or in the later treatises of Marcellus Empiricus? The