The use of minerals as pigments in art and on archaeological objects, from the use of ochre in prehistoric caves to the elaborate transformation and use in ancient and modern artist palettes, is reviewed in this chapter. Starting from the purposes of the study of pigments, the chapter presents current trends in the study of coloured minerals in cultural heritage science. It emphasizes through the use of case studies the potential of these minerals in terms of information about former ways of life and especially the artistic techniques employed in ancient times. This information is gained through knowledge of geological and physicochemical processes acting on minerals and on artefacts produced by human activities. Some new trends are presented as the state of the art of how to master most of the methods and techniques useful for investigating our common cultural heritage.

From shell beads in the Palaeolithic and stone beads in the Neolithic to beautiful artificial gems in modern times, the history of gems has roughly paralleled that of humans. In the beginning, myths and folklore about the healing properties of gemstones dominated the story. Today, the story is about scientific techniques making larger or more colourful gems and newly discovered mineral deposits revealing gemstone treasures. In the western world the written history of precious and semiprecious stones begins with the On Stones of the Greek philosopher and naturalist Theophrastus ( ca . 315 BC) followed by the Natural History of the Roman historian Pliny (77 AD), which was the standard work on gems and minerals for more than a thousand years. The gemstones of the Old Testament and those of ancient East Asia tell their separate stories. Following a brief summary of these early works, this paper continues with individual descriptions of the major gems and semiprecious stones, focusing on their two most important attributes – colour and hardness – as well as where they are found. This is followed by a brief discussion of altered gems and a summary of modern interactions of gems and man. This paper concludes with some personal experiences of the author and a brief introduction to the geology of gem deposits.