A second edition, in two parts, of Volume 1 of this well-known reference series. This volume deals mainly with the disilcates and ring silicates including the epidote, melilite, cordierite, and tourmaline groups. In addition to the minerals dealt with in the first edition, some of the rarer but typical minerals in the calc-silicate rocks and the accessory minerals of nepheline-syenites and related rocks have been included. The orthosilicates, in particular the olivine, garnet and humite groups are covered in Volume 1A. In the years since the first edition was published, the quantity and scope of research on the disilicates and ring has grown enormously and has given rise to a wide variety of literature. This book, which has been completely rewritten and considerably expanded, summarizes the important research results and presents them in an organized fashion. Each mineral chapter is divided into sections on structure, chemistry, optical and physical properties, distinguishing features and paragenesis. Each chapter is headed by a tabulation of mineral data and a sketch showing optical orientation, and concludes with full references to the literature. Diagrams of the crystal structures are presented and are followed by a discussion of the structural features. The chemical sections include a large number of analyses from which structural formulae have been calculated, illustrating the chemical and paragenetical variation exhibited by each mineral; phase equilibria in relevant systems are fully considered. In the sections on optical and physical properties, particular attention is paid to the correlation of these properties with chemical composition. The principal modes of occurrence are described and discussed in the paragenesis sections; here again correlation with chemistry is emphasized. Also available: Rock Forming Minerals 3B: Layered Silicates Excluding Micas and Clay Minerals - ISBN 1862392595 Orthosilicates (Rock-Forming Minerals) - ISBN 1897799888 The Geological Society of LondonFounded in 1807, the Geological Society of London is the oldest geological society in the world, and one of the largest publishers in the Earth sciences.The Society publishes a wide range of high-quality peer-reviewed titles for academics and professionals working in the geosciences, and enjoys an enviable international reputation for the quality of its work.The many areas in which we publish in include:-Petroleum geology-Tectonics, structural geology and geodynamics-Stratigraphy, sedimentology and paleontology-Volcanology, magmatic studies and geochemistry-Remote sensing-History of geology-Regional geology guides