The book reviews the geological, mineralogical, geochemical and petrological characteristics of indium-bearing ore deposits. Furthermore it develops a general metallogenic concept for indium in identifying the essential enrichment processes and their economic significance. It represents the first comprehensive study on the metallogeny of indium and covers economic aspects including production and use. Careful geological and mineralogical descriptions are given for representative examples of different deposit types with most significant characteristics being summarized at the end of each chapter.

Research on base metal sulfide deposits is among the oldest and best-documented subjects of economic geologists worldwide, c- sidering that copper was first mined about 3000 years ago on the island of Cyprus. During the past 10 years, after the exciting discovery of active sulfide formation on the modem ocean floor, a considerable flow of new ideas has stimulated and influenced the discussion of o- forming processes for copper-zinc-Iead sulfides in sedimentary and volcanic environments. The development of new genetic concepts consequently led to reinterpretation of some apparently well-est- lished formation models. This Proceedings Volume contains a collection of carefully selected papers on current research on the geology and metallogeny of base metal sulfide deposits presented as oral or poster contri- tions at the DMG (Deutsche Mineralogische Gesellschaft) - GDMB (Gesellschaft Deutscher Metallhiitten- und Bergleute - Fachsektion Lagerstiittenforschung) - SGA (Society of Geology Applied to Mineral Deposits) Joint Meeting on Ore Deposits in Aachen, Federal Republic of Germany, September 16-19, 1985. Base metal sulfide deposits with different ore compositions occur in a wide variety of geological and lithological settings of almost any age. This has been taken into account in organizing this volume along the lines of classical host-rock classification. The first group of contributions focuses on sediment-hosted base metal sulfide deposits including examples of Kupferschiefer and Copperbelt-type, as well as lead-zinc mineralization in car- nate host rocks.

The extraordinary growth of the computer and semiconductor industries and the increasing consumption of indium in these technologies in recent years have placed major constraints on current and future reserves of this metal. In the past, geoscientists have noticed the occurrence of indium in a large variety of ore de posits and detailed geochemical and mineralogical work is available for a few ex amples. However, despite the current technological interest, there is no compre hensive textbook that deals with all aspects of indium mineralization and economics. The present study attempts to develop a general metallogenic concept for indium in identifying the essential enrichment processes and their economic significance. The study 'Indium Geology, Mineralogy, and Economics' was commissioned and funded by the German Federal Institute for Geosciences and Natural Re sources (BGR Hannover) and is a contribution to the research program 'BGR 2000 - Raw Materials with Short Lifetime Reserves'. This program focuses on raw materials with known reserves confined to the next 20-25 years at static de mand. The future availability of reserves is usually estimated by dividing the known reserves by the current annual consumption. In fact, lifetimes of reserves are inappropriate measures because they depend on many parameters and there fore represent a "snapshot" of a dynamic system. In order to provide a sustainable use of raw materials with short lifetime reserves, a significantly higher amount of innovation is needed compared to raw materials with long lifetime reserves."