ALBERT

Description / Table of Contents: At the time of the first printing (1996), interest in the element boron was growing rapidly. We felt that it was an opportune moment to ask investigators active in research on boron to review developments in their respective fields so that readers could learn what was-and wasn't-known about boron and its minerals, geochemistry and petrology. Since 1996, interest in boron has, if anything, increased, and continued demand for the Reviews in Mineralogy "boron bible" has motivated the Mineralogical Society of America to reprint the volume. Demand is reflected in citations, and according to ISI's Science Citation Index, the number of citations since publication to the volume is about 380, with some individual chapters having been cited as many as 44 times. In preparation for this printing, authors of 15 of the 19 original chapters have updated, corrected or added to their chapters within the constraints that no pages be added. Most addenda are bibliographies of literature published since 1996; a few also include summaries of significant findings. Addenda for each chapter follow the chapter, except for those for Chapters 1 and 2, which are merged onto pages 115-116 and 385. A table of new B-minerals since 1996 is given on p. 28, and many modifications were made to the table (p. 7-27) of B-minerals known prior to 1996 (corrections to formulae, mineral names, localities, etc.). Similar up-datings of Table 1 (p. 223) in Chapter 5 and numerous tables in Chapter 9 (p. 387) were undertaken, and Figure 15 in Chapter 11 (p. 619), which-embarrassingly-was missing from the first printing, has been supplied. Addenda to Chapter 13 are introduced on p. 744 and completed on p. 863 and 864. The following salient developments in research related to B are mentioned in the addenda: New minerals. Twenty-two boron minerals have been or are about to be described, and four more have been approved by the International Mineralogical Association, representing an increase of 10%, comparable to the increase in the number of all new minerals described during the same period (Anovitz and Grew, Chapter 1) Tourmaline group. In addition to four new tourmaline species, a new classification has been proposed. Another tourmaline, olenite, has been shown to contain substantial amounts of excess B in tetrahedral coordination, a finding that has revolutionized our view of tourmaline crystal chemistry (Werding and Schreyer, Chapter 3; references in addendum to Henry and Dutrow, Chapter 10). Boron isotopes. New techniques for measuring isotope ratios using secondary ion mass spectroscopy (SIMS) with the ion microprobe open up new opportunities for in situ analyses of individual grains and fluid inclusions (Hervig, Chapter 16). Boron isotopes have found applications in paleoceanography and thus add to the tools available for the study of past climates (Palmer and Swihart, Chapter 13). One of the major questions facing the use of hydrogeochemical models is whether or not they can be used with confidence to predict future evolution of groundwater systems. There is much controversy concerning the validity and uncertainties of non-reactive fluid flow systems. Adding chemical interaction to these flow models only confounds the problem. Although such models may accurately integrate the governing physical and chemical equations, many uncertainties are inherent in characterizing the natural system itself. These systems are inherently heterogeneous on a variety of scales rendering it impossible to know precisely the many details of the flow system and chemical composition of the host rock. Other properties of natural systems such as permeability and mineral surface area, to name just two, may never be known with any great precision, and in fact may be unknowable. Because of these uncertainties, it remains an open question as to what extent numerical models of groundwater flow and reactive transport wilI be useful in making accurate quantitative predictions. Nevertheless, reactive transport models should be able to predict the outcome for the particular representation of the porous medium used in the model. Finally, it should be mentioned that numerical models are often our only recourse to analyze such environmental problems as safe disposal of nuclear waste where predictions must be carried out over geologic time spans. Without such models it would be impossible to analyze such systems, because they involve times too long to perform laboratory experiments. The results of model calculations may affect important political decisions that must be made. Therefore, it is all the more important that models be applied and tested in diverse environments so that confidence and understanding of the limitations and strengths of model predictions are understood before irreversible decisions are made that could adversely affect generations to come.

Description / Table of Contents: The publication of this volume occurs at the one-hundredth anniversary of 1905, which has been called the annus mirabilus because it was the year of a number of enormous scientific advances. Among them are four papers by Albert Einstein explaining (among other things) Brownian motion, the photoelectric effect, the special theory of relativity, and the equation E = mc2. Also of significance in 1905 was the first application of another major advance in physics, which dramatically changed the fields of Earth and planetary science. In March of 1905 (and published the following year), Ernest Rutherford presented the following in the Silliman Lectures at Yale: "The helium observed in the radioactive minerals is almost certainly due to its production from the radium and other radioactive substances contained therein. If the rate of production of helium from known weights of the different radioelements were experimentally known, it should thus be possible to determine the interval required for the production of the amount of helium observed in radioactive minerals, or, in other words, to determine the age of the mineral." Rutherford E (1906) Radioactive Transformations. Charles Scriber's Sons, NY Thus radioisotopic geochronology was born, almost immediately shattering centuries of speculative conjectures and estimates and laying the foundation for establishment of the geologic timescale, the age of the Earth and meteorites, and a quantitative understanding of the rates of processes ranging from nebular condensation to Quaternary glaciations. There is an important subplot to the historical development of radioisotopic dating over the last hundred years, which, ironically, arises directly from the subsequent history of the U-He dating method Rutherford described in 1905. Almost as soon as radioisotopic dating was invented, it was recognized that the U-He [or later the (U-Th)/He method], provided ages that were often far younger than those allowed by stratigraphic correlations or other techniques such as U/Pb dating. Clearly, as R.J. Strutt noted in 1910, He ages only provided "minimum values, because helium leaks out from the mineral, to what extent it is impossible to say" (Strutt, 1910, Proc Roy Soc Lond, Ser A 84:379-388). For several decades most attention was diverted to U/Pb and other techniques better suited to measurement of crystallization ages and establishment of the geologic timescale. Gradually it became clear that other radioisotopic systems such as K/Ar and later fission-track also provided ages that were clearly younger than formation ages. In 1910 it may have been impossible to say the extent to which He (or most other elements) leaked out of minerals, but eventually a growing understanding of thermally-activated diffusion and annealing began to shed light on the significance of such ages. The recognition that some systems can provide cooling, rather than formation, ages, was gradual and diachronous across radioisotopic systems. Most of the heavy lifting in this regard was accomplished by researchers working on the interpretation of K/Ar and fission-track ages. Ironically, Rutherfordπs He-based radioisotopic system was one of the last to be quantitatively interpreted as a thermochronometer, and has been added to K/Ar (including 40Ar/39Ar) and fission-track methods as important for constraining the medium- to low-temperature thermal histories of rocks and minerals. Thermochronology has had a slow and sometimes fitful maturation from what were once troubling age discrepancies and poorly-understood open-system behaviors, into a powerful branch of geochronology applied by Earth scientists from diverse fields. Cooling ages, coupled with quantitative understanding of crystal-scale kinetic phenomena and crustal- or landscape-scale interpretational models now provide an enormous range of insights into tectonics, geomorphology, and subjects of other fields. At the same time, blossoming of lower temperature thermochronometric approaches has inspired new perspectives into the detailed behavior of higher temperature systems that previously may have been primarily used for establishing formation ages. Increased recognition of the importance of thermal histories, combined with improved analytical precision, has motivated progress in understanding the thermochronologic behavior of U/Pb, Sm/Nd, Lu/Hf, and other systems in a wide range of minerals, filling out the temperature range accessible by thermochronologic approaches. Thus the maturation of low- and medium-temperature thermochronology has led to a fuller understanding of the significance of radioisotopic ages in general, and to one degree or another has permeated most of geochronology. Except in rare cases, the goal of thermochronology is not thermal histories themselves, but rather the geologic processes responsible for them. Thermochronometers are now routinely used for quantifying exhumation histories (tectonic or erosional), magmatism, or landscape evolution. As thermochronology has matured, so have model and interpretational approaches used to convert thermal histories into these more useful geologic histories. Low-temperature thermochronology has been especially important in this regard, as knowledge of thermal processes in the uppermost few kilometers of the crust require consideration of coupled interactions of tectonic, geodynamic, and surface processes. Exciting new developments in these fields in turn drive improved thermochronologic methods and innovative sampling approaches. The chapters This volume presents 22 chapters covering many of the important modern aspects of thermochronology. The coverage of the chapters ranges widely, including historical perspective, analytical techniques, kinetics and calibrations, modeling approaches, and interpretational methods. In general, the chapters focus on intermediate- to low-temperature thermochronometry, though some chapters cover higher temperature methods such as monazite U/Pb closure profiles, and the same theory and approaches used in low-temperature thermochronometry are generally applicable to higher temperature systems. The widely used low- to medium-temperature thermochronometric systems are reviewed in detail in these chapters, but while there are numerous chapters reviewing various aspects of the apatite (U-Th)/He system, there is no chapter singularly devoted to it, partly because of several previous reviews recently published on this topic. Chapter 1 by Reiners, Ehlers, and Zeitler provides a perspective on the history of thermochronology, comments on modern work in this field and general lessons on the potential for noise to be turned into signal. This chapter also provides a summary of the current challenges, unresolved issues, and most exciting prospects in the field. Much of the modern understanding of kinetic controls on apparent ages, thermal histories, and sampling approaches comes from decades of progress in fission-track dating, a method that remains as essential as ever, partly because of the power of track-length measurements and the depth of (at least empirical) understanding of the kinetics of track annealing. Tagami, Donelick and OπSullivan review the fundamentals of modern fission-track dating (Chapter 2). Two of the most commonly dated, well-understood, and powerful minerals dated by fission-track methods are apatite and zircon, and the specifics of modern methods for these systems and their kinetics are reviewed by Donelick, OπSullivan, and Ketcham (Chapter 3), and Tagami (Chapter 4). Although 40Ar/39Ar and (U-Th)/He dating methods followed somewhat different paths to their modern thermochronologic incarnations, they have many features in common, especially in the kinetics of diffusion and closure. Zeitler and Harrison review the concepts underlying both 40Ar/39Ar and (U-Th)/He methods (Chapter 5). Zircon was one of the first minerals dated by the (U-Th)/He method, but has only just begun to be used for thermochronometry of both bedrock and detrital samples, as reviewed by Reiners (Chapter 6). Continuous time-temperature paths from intracrystalline variations of radiogenic Ar proven perhaps the most powerful of all thermochronologic approaches, and an innovative analogous approach in He dating (4He/3He thermochronometry) is revealing remarkably powerful constraints on the extreme low temperature end of thermal histories, as reviewed by Shuster and Farley (Chapter 7). Thermochronology of detrital minerals provides unique constraints on the long-term evolution of orogens, sediment provenance, and depositional age constraints, to name a few. Bernet and Garver (Chapter 8) review the essentials of detrital zircon fission-track dating, one of the most venerable and robust of detrital thermochronometers, and in Chapter 9, Hodges, Ruhl, Wobus, and Pringle review the use of 40Ar/39Ar dating of detrital minerals, demonstrating the power of detrital muscovite ages in illuminating variations in exhumation rates in catchments over broad landscapes. (U-Th)/He thermochronometry presents several unique interpretational challenges besides new kinetics and low temperature sensitivity. One of these is long-alpha stopping distances, and its coupling with diffusion and U-Th zonation in age corrections. Dunai reviews modeling approaches to deal with these issues in interpreting low-temperature thermal histories (Chapter 10). Ketcham (Chapter 11) reviews the theory and calibration of both forward and inverse models of thermal histories from fission-track and (U-Th)/He data, and makes some important points about the interpretations of such models. Translating thermal histories into exhumational histories and their tectonic or geomorphic significance across a landscape requires quantitative understanding of the thermal structure of the crust and how it is perturbed, a review of which is presented by Ehlers (Chapter 12). Braun (Chapter 13) illustrates the power of low-temperature thermochronometry to constrain topographic evolution of landscapes over time, using PECUBE. Gallagher, Stephenson, Brown, Holmes, and Ballester present a novel method of inverse modeling of fission-track and (U-Th)/He data for thermal histories over landscapes (Chapter 14). Continuous time-temperature paths from closure profiles or their step-heating-derived equivalents are, to some degree, the holy grail of thermochronology. Harrison, Zeitler, Grove, and Lovera (Chapter 15) provide a review of the theory, measurement, and interpretation of continuous thermal histories at both intermediate and high temperatures, derived from both K-feldspar 40Ar/39Ar and monazite U/Pb dating. Extensional orogens provide a special challenge and opportunity for thermochronometry because tectonic exhumation by footwall unroofing often outstrips erosional exhumation, and often occurs at high rates. As Stockli shows (Chapter 16) thermochronology in these setting provides opportunities to measure rates of a number of important processes, as well as obtain a snapshot of crustal thermal structure and its imprint on thermochronometers with varying closure temperatures. Spotila (Chapter 17) reviews the use of thermochronology applied to tectonic geomorphology in a wide range of orogenic settings, introducing the concept of denudational maturity. Thermochronology has found great utility in economic geology, and newly developed approaches pose great potential in this area, and shown by McInnes, Evans, Fu, and Garwin in their review of the use and modeling of thermochronology of hydrothermal ore deposits (Chapter 18). The thermal histories of sedimentary basins are also critical to understanding thermal maturation of hydrocarbons, but are also critical for understanding basin formation, erosional histories of source regions, fluid flow, and climate change and other temporal signals preserved in sedimentary rocks. Armstrong (Chapter 19) reviews these issues and the use of thermochronology in deducing the thermal histories of sedimentary basins. Drawing on large datasets of bedrock apatite fission-track dates, Kohn, Gleadow, Brown, Gallagher, Lorencak, and Noble demonstrate the power of modeling, and, importantly, effectively visualizing, integrated thermotectonic and denudational histories over large regions (Chapter 20). Thermal histories of meteorites provide constraints on a wide range of fundamentally important processes, including nebular condensation and early solar-system metamorphic histories, and the dynamics of interplanetary collisions and shock metamorphism. Min reviews thermochronologic approaches to understanding meteorite thermal histories (Chapter 21), including new methods and approaches. Finally, the importance of robust models with which to interpret thermochronologic data is underscored by the review of the Software for Interpretation and Analysis of Thermochronologic Data (Chapter 22), summarized and compiled by Ehlers, for programs associated with the work of authors in this volume and others.

Description / Table of Contents: The importance of sulfide minerals in ores has long been, and continues to be, a major reason for the interest of mineralogists and geochemists in these materials. Determining the fundamental chemistry of sulfides is key to understanding their conditions of formation and, hence, the geological processes by which certain ore deposits have formed. This, in turn, may inform the strategies used in exploration for such deposits and their subsequent exploitation. In this context, knowledge of structures, stabilities, phase relations and transformations, together with the relevant thermodynamic and kinetic data, is critical. As with many geochemical systems, much can also be learned from isotopic studies. The practical contributions of mineralogists and geochemists to sulfide studies extend beyond areas related to geological applications. The mining of sulfide ores, to satisfy ever increasing world demand for metals, now involves extracting very large volumes of rock that contains a few percent at most (and commonly less than one percent) of the metal being mined. This is true of relatively low value metals such as copper; for the precious metals commonly occurring as sulfides, or associated with them, the mineable concentrations (grades) are very much lower. The "as-mined" ores therefore require extensive processing in order to produce a concentrate with a much higher percentage content of the metal being extracted. Such mineral processing (beneficiation) involves crushing and grinding of the ores to a very fine grain size in order to liberate the valuable metal-bearing (sulfide) minerals which can then be concentrated. In some cases, the metalliferous (sulfide) minerals may have specific electrical or magnetic properties that can be exploited to enable separation and, hence, concentration. More commonly, froth flotation is used, whereby the surfaces of particles of a particular mineral phase are rendered water repellent by the addition of chemical reagents and hence are attracted to air bubbles pulsed through a mineral particle-water-reagent pulp. An understanding of the surface chemistry and surface reactivity of sulfide minerals is central to this major industrial process and, of course, knowledge of electrical and magnetic properties is very important in cases where those particular properties can be utilized. In the years since the publication of the first ever Reviews in Mineralogy volume (1974, at that time called MSA "Short Course Notes") which was entitled Sulfide Mineralogy, sulfides have become a focus of research interest for reasons centering on at least two other areas in addition to their key role in ore deposit studies and mineral processing technology. It is in these two new areas that much of the research on sulfides has been concentrated in recent years. The first of these areas relates to the capacity of sulfides to react with natural waters and acidify them; the resulting Acid Rock Drainage (ARD), or Acid Mine Drainage (AMD) where the sulfides are the waste products of mining, has the capacity to damage or destroy vegetation, fish and other aquatic life forms. These acid waters may also accelerate the dissolution of associated minerals containing potentially toxic elements (e.g., As, Pb, Cd, Hg, etc.) and these may, in turn, cause environmental damage. The much greater public awareness of the need to prevent or control AMD and toxic metal pollution has led to regulation and legislation in many parts of the world, and to the funding of research programs aimed at a greater understanding of the factors controlling the breakdown of sulfide minerals. We begin with a review of analytical methods for measuring and calibrating water contents in nominally anhydrous minerals by George Rossman. While infrared spectroscopy is still the most sensitive and most convenient method for detecting water in minerals, it is not intrinsically quantitative but requires calibration by some other, independent analytical method, such as nuclear reaction analysis, hydrogen manometry, or SIMS. A particular advantage of infrared spectroscopy, however, is the fact that it does not only probe the concentration, but also the structure of hydrous species in a mineral and in many cases the precise location of a proton in a mineral structure can be worked out based on infrared spectra alone. The methods and principles behind this are reviewed by Eugen Libowitzky and Anton Beran, with many illustrative examples. Compared to infrared spectroscopy, NMR is much less used in studying hydrogen in minerals, mostly due to its lower sensitivity, the requirement of samples free of paramagnetic ions such as Fe2+ and because of the more complicated instrumentation required for NMR measurements. However, NMR could be very useful under some circumstances. It could detect any hydrogen species in a sample, including such species as H2 that would be invisible with infrared. Potential applications of NMR to the study of hydrogen in minerals are reviewed by Simon Kohn. While structural models of "water" in minerals have already been deduced from infrared spectra several decades ago, in recent years atomistic modeling has become a powerful tool for predicting potential sites for hydrogen in minerals. The review by Kate Wright gives an overview over both quantum mechanical methods and classical methods based on interatomic potentials. Joseph Smyth then summarizes the crystal chemistry of hydrogen in high-pressure silicate and oxide minerals. As a general rule, the incorporation of hydrogen is not controlled by the size of potential sites in the crystal lattice; rather, the protons will preferentially attach to oxygen atoms that are electrostatically underbonded, such as the non-silicate oxygen atoms in some high-pressure phases. Moreover, heterovalent substitutions, e.g., the substitution of Al3+ for Si4+, can have a major effect on the incorporation of hydrogen. The second reason for even greater research interest in sulfide minerals arose initially from the discoveries of active hydrothermal systems in the deep oceans. The presence of life forms that have chemical rather than photosynthetic metabolisms, and that occur in association with newly-forming sulfides, has encouraged research on the potential of sulfide surfaces in catalyzing the reactions leading to assembling of the complex molecules needed for life on Earth. These developments have been associated with a great upsurge of interest in the interactions between microbes and minerals, and in the role that minerals can play in biological systems. In the rapidly growing field of geomicrobiology, metal sulfides are of major interest. This interest is related to a variety of processes including, for example, those where bacteria interact with sulfides as part of their metabolic activity and cause chemical changes such as oxidation or reduction, or those in which biogenic sulfide minerals perform a specific function, such as that of navigation in magnetotactic bacteria. The development of research in areas such as geomicrobiology and environmental mineralogy and geochemistry, is also leading to a greater appreciation of the role of sulfides (particularly the iron sulfides) in the geochemical cycling of the elements at or near the surface of the Earth. For example, the iron sulfides precipitated in the reducing environments beneath the surface of modern sediments in many estuarine areas may play a key role in the trapping of toxic metals and other pollutants. In our understanding of "Earth Systems," geochemical processes involving metal sulfides are an important part of the story. The main objective of the present text is to provide an up-to-date review of sulfide mineralogy and geochemistry. The emphasis is, therefore, on such topics as crystal structure and classification, electrical and magnetic properties, spectroscopic studies, chemical bonding, high and low temperature phase relations, thermochemistry, and stable isotope systematics. In the context of this book, emphasis is on metal sulfides sensu stricto where only the compounds of sulfur with one or more metals are considered. Where it is appropriate for comparison, there is brief discussion of the selenide or telluride analogs of the metal sulfides. When discussing crystal structures and structural relationships, the sulfosalt minerals as well as the sulfides are considered in some detail (see Chapter 2; also for definition of the term "sulfosalt"). However, in other chapters there is only limited discussion of sulfosalts, in part because there is little information available beyond knowledge of chemical composition and crystal structure. Given the dramatic developments in areas of research that were virtually non-existent at the time of the earlier reviews, major sections have been added here on sulfide mineral surface chemistry and reactivity, formation and transformation of metal-sulfur clusters and nanoparticles, modeling of hydrothermal precipitation, and on sulfides in biosystems. However, it should be emphasized that the growth in the literature on certain aspects of sulfide mineralogy over the past 20 years or so has been such that comprehensive coverage is not possible in a single volume. Thus, the general area of "sulfides in biosystems" is probably worthy of a volume in itself, and "environmental sulfide geochemistry" (including topics such as oxidative breakdown of sulfides) is another area where far more could have been written. In selecting areas for detailed coverage in this volume, we have been mindful of the existence of other relatively recent review volumes, including those in the RiMG series. It has also been our intention not to cover any aspects of the natural occurrence, textural or paragenetic relationships involving sulfides. This is published information that, although it may be supplemented by new observations, is likely to remain useful for a long period and largely not be superceded by later work. In the following chapters, the crystal structures, electrical and magnetic properties, spectroscopic studies, chemical bonding, thermochemistry, phase relations, solution chemistry, surface structure and chemistry, hydrothermal precipitation processes, sulfur isotope geochemistry and geobiology of metal sulfides are reviewed. Makovicky (Chapter 2) discusses the crystal structures and structural classification of sulfides and other chalcogenides (including the sulfosalts) in terms of the relationships between structural units. This very comprehensive survey, using a rather different and complementary approach to that used in previous review volumes, shows the great diversity of sulfide structures and the wealth of materials that remain to be characterized in detail. These materials include rare minerals, and synthetic sulfides that may represent as yet undescribed minerals. Pearce, Pattrick and Vaughan (Chapter 3) review the electrical and magnetic properties of sulfides, discussing the importance of this aspect of the sulfides to any understanding of their electronic structures (chemical bonding) and to applications ranging from geophysical prospecting and mineral extraction to geomagnetic and palaeomagnetic studies. Rapidly developing new areas of interest discussed include studies of the distinctive properties of sulfide nanoparticles. Wincott and Vaughan (Chapter 4) then outline the spectroscopic methods employed to study the crystal chemistry and electronic structures of sulfides. These range from UV-visible through infrared and Raman spectroscopies, to X-ray emission, photoemission and absorption, and to nuclear spectroscopies. Chemical bonding (electronic structure) in sulfides is the subject of the following chapter by Vaughan and Rosso (Chapter 5), a topic which draws on knowledge of electrical and magnetic properties and spectroscopic data as experimental input, as well as on a range of rapidly developing computational methods. Attention then turns to the thermochemistry of sulfides in a chapter by Sack and Ebel (Chapter 6) which is followed by discussion of phase equilibria at high temperatures in the review by Fleet (Chapter 7). Sulfides in aqueous systems, with emphasis on solution complexes and clusters, forms the subject matter of the chapter written by Rickard and Luther (Chapter 8). Sulfide mineral surfaces are the focus of the next two chapters, both by Rosso and Vaughan. The first of these chapters (Chapter 9) addresses characterization of the pristine sulfide surface, its structure and chemistry; the second (Chapter 10) concerns surface reactivity, including redox reactions, sorption phenomena, and the catalytic activity of sulfide surfaces. Reed and Palandri (Chapter 11) show in the next chapter how much can now be achieved in attempting to predict processes of sulfide precipitation in hydrothermal systems. The final chapters deal with two distinctive areas of sulfide mineralogy and geochemistry. Seal (Chapter 12) presents a comprehensive account of the theory and applications of sulfur isotope geochemistry; sulfur isotope fractionation can provide the key to understanding the natural processes of formation of sulfide deposits. In the final chapter, Posfai and Dunin-Borkowski (Chapter 13) review the rapidly developing area of sulfides in biosystems, discussing aspects of both sulfide mineral-microbe interactions and biomineralization processes involving sulfides.

Description / Table of Contents: This volume contains the contributions presented at a short course held in Golden, Colorado, October 25-27, 1996 in conjunction with the Mineralogical Society of America's (MSA) Annual Meeting with the Geological Society of America in Denver, Colorado. The field of reactive transport within the Earth Sciences is a highly multidisciplinary area of research. The field encompasses a number of diverse disciplines including geochemistry, geology, physics, chemistry, hydrology, and engineering. The literature on the subject is similarly spread out as can be seen by a perusal of the bibliographies at the end of the chapters in this volume. Because these distinct disciplines have evolved largely independently of one another, their respective treatments of reactive transport in the Earth Sciences are based on different terminologies, assumptions, and levels of mathematical rigor. This volume and the short course which accompanies it, is an attempt to some extent bridge the gap between these different disciplines by bringing together authors and students from different backgrounds. A wide variety of geochemical processes including such diverse phenomena as the transport of radiogenic and toxic waste products, diagenesis, hydrothermal ore deposit formation, and metamorphism are the result of reactive transport in the subsurface. Such systems can be viewed as open bio-geochemical reactors where chemical change is driven by the interactions between migrating fluids, solid phases, and organisms. The evolution of these systems involves diverse processes including fluid flow, chemical reaction, and solute transport, each with differing characteristic time scales. This volume focuses on methods to describe the extent and consequences of reactive flow and transport in natural subsurface systems. Our ability to quantify reactive transport in natural systems has advanced dramatically over the past decade. Much of this advance is due to the exponential increase in computer computational power over the past generation-geochemical calculations that took years to perform in 1970 can be performed in seconds in 1996. Taking advantage of this increase of computational power, numerous comprehensive reactive transport models have been developed and applied to natural phenomena. These models can be used either qualitatively or qualitatively to provide insight into natural phenomena. Quantitative models force the investigator to validate or invalidate ideas by putting real numbers into an often vague hypothesis and thereby starting the thought process along a path that may result in acceptance, rejection, or modification of the original hypothesis. Used qualitatively, models provide. insight into the general features of a particular phenomenon, rather than specific details. One of the major questions facing the use of hydrogeochemical models is whether or not they can be used with confidence to predict future evolution of groundwater systems. There is much controversy concerning the validity and uncertainties of non-reactive fluid flow systems. Adding chemical interaction to these flow models only confounds the problem. Although such models may accurately integrate the governing physical and chemical equations, many uncertainties are inherent in characterizing the natural system itself. These systems are inherently heterogeneous on a variety of scales rendering it impossible to know precisely the many details of the flow system and chemical composition of the host rock. Other properties of natural systems such as permeability and mineral surface area, to name just two, may never be known with any great precision, and in fact may be unknowable. Because of these uncertainties, it remains an open question as to what extent numerical models of groundwater flow and reactive transport wilI be useful in making accurate quantitative predictions. Nevertheless, reactive transport models should be able to predict the outcome for the particular representation of the porous medium used in the model. Finally, it should be mentioned that numerical models are often our only recourse to analyze such environmental problems as safe disposal of nuclear waste where predictions must be carried out over geologic time spans. Without such models it would be impossible to analyze such systems, because they involve times too long to perform laboratory experiments. The results of model calculations may affect important political decisions that must be made. Therefore, it is all the more important that models be applied and tested in diverse environments so that confidence and understanding of the limitations and strengths of model predictions are understood before irreversible decisions are made that could adversely affect generations to come.

Description / Table of Contents: With the ever increasing spatial resolution in the characterization of microstructures, textures and chemical as well as isotopic patterns and the continuously improving sensitivity and precision in mineral chemical and isotopic analysis, increasing evidence has emerged indicating that phase relations in rocks from high-temperature environments may be modified during exhumation and cooling and that the original equilibrium phase relations may not have been preserved or that equilibrium may never have been attained fully even at high temperatures. This volume accompanies an EMU School intended bring contemporary research on mineral reaction kinetics to the attention of young researchers and to put it into the context of recent developments in related disciplines. The school and the accompanying volume cannot give a comprehensive review of the current state of geomaterials research. Rather a selection of topics, methods and concepts, which the contributors deem currently most relevant and instructive, is presented. The aim is to provide a methodologically sound insight into the theoretical foundations of mineral reaction kinetics, to help students to become acquainted with contemporary methods in experimentation and analytical techniques, and to give worked examples that illustrate recent advances in geoscience based on an improved characterization and understanding of mineral and rock systems.

Description / Table of Contents: In Materials Science, investigations aiming to prepare new types of molecular sieves (porous materials) have opened a productive field of research inspired by the crystal structures of minerals. These new molecular sieves are distinct from zeolites in that they have different kinds of polyhedra that build up their structures. Of particular interest are the new molecular sieves characterized by a mixed "octahedral"-tetrahedral framework (heteropolyhedral frameworks), instead of a purely tetrahedral framework as in zeolites. Heteropolyhedral compounds have been extensively studied since the early 1990's, with particular attention having been focused on titanosilicates, such as ETS-4 (synthetic analog of the mineral zorite) and ETS-10. However, titanosilicates are not the only representatives of novel microporous mineral phases. The search for "octahedral"-tetrahedral silicates was extended to metals other than titanium, for instance, the zirconosilicates with the preparation of synthetic counterparts of the minerals gaidonnayite, petarasite and umbite. Many microporous heteropolyhedral compounds containing metals such as Nb, V, Sn, Ca and lanthanides, have been reported and a wide number of distinct structural types (e.g., rhodesite-delhayelite and tobermorite) have been synthesized and structurally characterized. Moreover, the potential applications of these novel materials have been evaluated, particularly in the areas of catalysis, separation of molecular species, ion exchange and optical and magnetic properties. A comprehensive review of the mineralogical, structural, chemical and crystal-chemical studies carried on natural phases may be extremely useful to inspire and favor investigations on analogs or related synthetic materials. A similar synergy between mineralogists and materials scientists already occurred in the "classical" case of zeolites, in which the wide and deep structural and crystal-chemical knowledge accumulated in the study of the natural phases was extraordinarily useful to the chemists who are active in the field of molecular sieves. In particular, the structural investigation of the natural phases may be extremely rewarding and helpful in orienting the work of synthesis and in understanding the nature of the synthetic products, for the following reasons: Whereas rarely the crystalline synthetic products are suitable for single-crystal structural investigations, the natural counterparts are often well crystallized. Crystallization in nature occurs from chemical systems characterized by a wide compositional range, thus producing compounds with a very rich and variable crystal chemistry, which may provide precious information, suggesting possible substituting elements and addressing the synthetic work in a very productive way. The present volume follows a meeting on "Micro- and mesoporous mineral phases" (Rome, December 6-7, 2004) that was jointly organized by the Accademia Nazionale dei Lincei (ANL) and the International Union of Crystallography (IUCr) via its Commission on Inorganic and Mineral Structures (CIMS). The meeting was convened by Fausto Calderazzo, Giovanni Ferraris, Stefano Merlino and Annibale Mottana and financially supported by several other organizations representing both Mineralogy (e.g., the International Mineralogical Association and the European Mineralogical Union) and Crystallography (e.g., the European Crystallographic Association and the Italian Association of Crystallography). To participants, ANL staff, organizations, and, in general, all involved persons, our sincere acknowledgments; in particular, we are grateful to Annibale Mottana who was able to convince the ANL Academicians to schedule and support the meeting. This volume of the RiMG series highlights the present knowledge on micro- and mesoporous mineral phases, with focus on their crystal-chemical aspects, occurrence and porous activity in nature and experiments. As zeolites are the matter of numerous ad hoc meetings and books - including two volumes in this series - they do not specifically appear in the present volume. The phases of the sodalite and cancrinite-davyne groups, which mineralogists consider distinct from zeolites, are instead considered (in the order, chapter 7 by W. Depmeier and part of chapter 8 by E. Bonaccorsi and S. Merlino, respectively). The first two chapters of the volume cover general aspects of porous materials. This includes the application of the IUPAC nomenclature developed for ordered porous materials to non-zeolite mineral phases (L.B. McCusker, chapter 1) and the extension to heteropolyhedral structures of a topological description by using nodes representing the coordination polyhedra (S.V. Krivovichev, chapter 2). Chapters from 3 to 7 are dedicated to various groups of heteropolyhedral porous structures for which the authors emphasize some of the more general aspects according to their research specialization. G. Ferraris and A. Gula (chapter 3) put the emphasis on the modular aspects of well-known porous phases (such as sepiolite, palygorskite and rhodesite-related structures) as well as on heterophyllosilicates that may be not strictly porous phases (according to the definition given in chapter 1) but could be the starting basis for pillared materials. The porous mineral phases typical of hyperalkaline rocks (such as eudialytes and labuntsovites) are discussed by N.V. Chukanov and I.V. Pekov under their crystal-chemical (chapter 4) and minerogenetic (chapter 5) aspects showing the role of ion exchange during the geological evolution from primary to later phases, with experimental cation exchange data also being reported. J. Rocha and Z. Lin (chapter 6) emphasize how research on the synthesis of octahedral-pentahedral-tetrahedral framework silicates has been inspired and motivated by the many examples of such materials provided by nature; synthesis, structure and possible technological applications of a wide number of these materials are also described. Following chapters 7 and 8 - which besides the cancrinite-davyne group, presents the crystallographic features of the minerals in the tobermorite and gyrolite groups - M. Pasero (chapter 9) illustrates the topological and polysomatic aspects of the "tunnel oxides," a historical name applied to porous oxides related to MnO2, and reviews their main technological applications. The next two chapters (10 and 11) draw attention to "unexpected" porous materials like apatite and sulfides. T.J. White and his team (chapter 10) convincingly show that the apatite structure type displays porous properties, some of which are already exploited. Chapter 10 also contains two appendices that report crystal and synthesis data for hundreds of synthetic apatites, a number that demonstrates how wide the interest is for this class of compounds. E. Makovicky (chapter 11) analyzes the structures of natural and synthetic sulfides and selenides showing that, even if experimental work proving porous activity is practically still missing, several structure types display promising channels. Chapter 12, by M. Mellini, is the only one dedicated to mesoporous mineral phases - which are crystalline compounds with pores wider than 2 nm. Examples discussed are carbon nanotubes, fullerenes - which occur also in nature - chrysotile, opal and, moving from channels to cages, clathrates.

Description / Table of Contents: Since the dawn of life on earth, organisms have played roles in mineral formation in processes broadly known as biomineralization. This biologically-mediated organization of aqueous ions into amorphous and crystalline materials results in materials that are as simple as adventitious precipitates or as complex as exquisitely fabricated structures that meet specialized functionalities. The purpose of this volume of Reviews in Mineralogy and Geochemistry is to provide students and professionals in the earth sciences with a review that focuses upon the various processes by which organisms direct the formation of minerals. Our framework of examining biominerals from the viewpoints of major mineralization strategies distinguishes this volume from most previous reviews. The review begins by introducing the reader to over-arching principles that are needed to investigate biomineralization phenomena and shows the current state of knowledge regarding the major approaches to mineralization that organisms have developed over the course of Earth history. By exploring the complexities that underlie the "synthesis" of biogenic materials, and therefore the basis for how compositions and structures of biominerals are mediated (or not), we believe this volume will be instrumental in propelling studies of biomineralization to a new level of research questions that are grounded in an understanding of the underlying biological phenomena.

Description / Table of Contents: Geochemistry is a science that is based on an understanding of chemical processes in the earth. One of the principal tools available to the chemist for understanding systems at equilibrium is thermodynamics. The awareness and application of thermodynamic techniques has increased at a very fast pace in geosciences; in fact, one may be so bold as to say that thermodynamics in geology has reached the "mature" stage, although much future thermodynamic research is certainly needed. However, the natural processes in the earth are often sluggish enough that a particular system may not reach equilibrium. This observation is being supported constantly by new experimental and field data available to the geochemist e.g. the non-applicability of the phase rule in some assemblages, the compositional inhomogeneities of mineral grains, the partial reaction rims surrounding original minerals, the lack of isotopic equilibration or the absence of minerals (e.g. dolomite), which should be present according to thermodynamics. The need to apply kinetics has produced a large number of papers dealing with kinetics in geochemistry. As an initial response to this growing field, a conference on geochemical transport and kinetics was conducted at Airlie House, VA, in 1973, sponsored by the Carnegie Institution of Washington. The papers there dealt with several kinetic topics including diffusion, exsolution, metasomatism and metamorphic layering. Since 1973 the number of kinetic papers has continued to increase greatly. Therefore, the time is ripe for a Short Course in Kinetics, which brings together the fundamentals needed to explain field observations using kinetic data. It is hoped that this book may serve, not only as a reference for researchers dealing with the rates of geochemical processes, but also as a text in courses on geochemical kinetics. One of us has found this need of a text in teaching a graduate course on geochemical kinetics at Harvard and at Penn State during the past several years. Finally, it is our hope that the book may itself further even more research into the rates of geochemical processes and into the quantification of geochemical observations. The book is organized with a rough temperature gradient in mind, i.e. low temperature kinetics at the beginning and igneous kinetics at the end (no prejudices are intended with this scheme!). However, the topics in each chapter are general enough that they can be applied often to any geochemical domain: sedimentary, metamorphic or igneous. The theory of kinetics operates at two complementary levels: the phenomenological and the atomistic. The former relies on macroscopic variables (e.g. temperature or concentrations) to describe the rates of reactions or the rates of transport; the latter relates the rates to the basic forces operating between the particular atomic or molecular species of any system. This book deals with both descriptions of the kinetics of geochemical processes. Chapter one sets the framework for the phenomenological theory of reaction rates. If any geochemical reaction is to be described quantitatively, the rate law must be experimentally obtained in a kinetically sound manner and the reaction mechanism must be understood. This applies to heterogeneous fluid-rock reactions such as those occurring during metamorphism, hydrothermal alteration or weathering as well as to homogeneous reactions. Chapter 2 extends the theory to the global kinetics of geochemical cycles. This enables the kinetic concepts of stability and feedback to be applied to the cycling of elements in the many reservoirs of the earth. Chapter 3 applies the phenomenological treatment of chapter 1 to diagenesis and weathering. The rate of dissolution of minerals as well as the chemical evolution of pore waters are discussed. The atomistic basis of rates of reaction, transition state theory, is introduced in Chapter 4. Transition state theory can be applied to relate the rate constants of geochemical reactions to the atomic processes taking place. This includes not only homogeneous reactions but also reactions that occur at the surface of minerals. Chapter 5 discusses the theory of irreversible thermodynamics and its application to petrology. The use of the second law of thermodynamics along with the expressions for the rate of entropy production in a system have been used successfully since 1935 to describe kinetic phenomena. The chapter applies the concepts to the growth of minerals during metamorphism as well as to the formation of differentiated layers (banding) in petrology. Chapter 6 describes the phenomenological theory of diffusion both in aqueous solutions and in minerals. In particular, the multicomponent nature of diffusion and its consequence in natural systems is elaborated. Chapter 7 provides the atomistic basis for the rates of reactions in minerals. Understanding of the rates of diffusion, conduction, order-disorder reactions or exsolution in minerals depends on proper description of the defects in the various mineral structures. Chapter 8 provides the kinetic theory of crystal nucleation and growth. While many of the concepts in the chapter can be applied to aqueous systems, the emphasis is on igneous processes occurring during crystallization of a melt. To fully understand both the mineral composition as well as the texture of igneous rocks, the processes whereby new crystals form and grow must be quantified by using kinetic theory. Due to space and time limitations (kinetics!) some topics have not been covered in detail. In particular, the mathematical solution of diffusion or conduction equations is discussed very well by Crank in his book, Mathematics of Diffusion, and so is not covered to a great extent here. The treatment of fluid flow (e.g. convection) is also not covered in the text.

Description / Table of Contents: Although it includes some discussion of chemically complex reactions and the chemographic relationships among amphiboles and other rockforming minerals, most of Volume 9A of Reviews in Mineralogy treats amphiboles and other hydrous pyriboles as isolated systems. In contrast, Volume 9B is dedicated more to an exploration of the social life of amphiboles and the amphibole personality in real rocks and in the experimental petrology laboratory. The chemical complexity of amphibole, which Robinson et al., refer to as "a mineralogical shark in a sea of unsuspecting elements," permits amphiboles to occur in a very wide variety of rock types, under a large range of pressure and temperature conditions, and in association with an impressive number of other minerals. The description of amphibole petrology and of petrologists' attempts to understand amphibole phase relations are therefore not simple matters, as the length of this volume suggests. Although they do not cover every type of amphibole occurrence, it is hoped that the papers in this volume will provide the amphibole student and researcher with an up-to-date summary of the most important aspects of amphibole petrology. Volume 9B, Amphiboles: Petrology and Experimental Phase Relations, was begun in 1981 in preparation for the Short Course on Amphiboles and Other Hydrous Pyriboles presented at Erlanger, Kentucky, October 29 - November 1, 1981, prior to the annual meetings of the Geological Society of America and associated societies. Unfortunately, only the first chapter was in manuscript form at the time of the short course, and publication was delayed by one year.

Description / Table of Contents: This book and accompanying MSA short course was first considered in 1987 in response to what seemed to be a growing interest in the chemical reactions that take place at mineral-water interfaces. Now, in 1990, this area of work is firmly established as one of the major directions in mineralogical and geochemical research (see Chapter 1). We believe that there are two major reasons for this. The first is that there is a growing awareness within various earth science disciplines that interface chemistry is very important in many natural processes, i.e., these processes cannot be adequately described, much less understood, unless the role of interface chemistry is carefully considered. Perhaps the best illustration of this increase in awareness is the diverse backgrounds of the scientists who will be attending the short course. Participants have research interests in aqueous and environmental geochemistry, mineralogy, petrology, and crystallography. In the final list of participants, one-quarter are from outside the United States, and include scientists from Australia, Canada, England, France, Israel, The Netherlands, Sweden, and Switzerland. The second reason that this field is one of the major new research directions in the earth sciences is because many methods, both experimental and theoretical, have relatively recently become available to study mineral surfaces and mineral-water interfaces. Many important spectroscopic techniques now used routinely to characterize surfaces and interfaces were not available twenty years ago, and some were not available just five years ago. To emphasize the importance of these methods, two Nobel prizes were awarded in the 1980's to the developers of x-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM). We have directed ourselves and the other authors of this book to follow the general guidelines of writing for "Reviews in Mineralogy". However, for the subject of mineral-water interface geochemistry, this is not easy because the field is far from mature. Several chapters are not reviews in the traditional sense in that they cover research that is relatively recent for which a considerable amount of work remains. In any case, we believe that this book describes most of the important concepts and contributions that have driven mineral-water interface geochemistry to its present state. We begin in Chapter 1 with examples of the global importance of mineral-water interface reactions and a brief review of the contents of the entire book. Thereafter, we have divided the book into four sections, including atomistic approaches (Chapters 2- 3), adsorption (Chapters 4-8), precipitation and dissolution (Chapters 9-11), and oxidation-reduction reactions (Chapters 11-14).

Description / Table of Contents: We seek to understand the timing and processes by which our solar system formed and evolved. There are many ways to gain this understanding including theoretical calculations and remotely sensing planetary bodies with a number of techniques. However, there are a number of measurements that can only be made with planetary samples in hand. These samples can be studied in laboratories on Earth with the full range of high-precision analytical instruments available now or available in the future. The precisions and accuracies for analytical measurements in modern Earth-based laboratories are phenomenal. However, despite the fact that certain types of measurements can only be done with samples in hand, these samples will always be small in number and not necessarily representative of an entire planetary surface. Therefore, it is necessary that the planetary material scientists work hand-in-hand with the remote sensing community to combine both types of data sets. This exercise is in fact now taking place through an initiative of NASA's Curation and Analysis Planning Team for Extraterrestrial Materials (CAPTEM). This initiative is named "New Views of the Moon: Integrated Remotely Sensed, Geophysical, and Sample Datasets." As preliminary results of the Lunar Prospector mission become available, and with the important results of the Galileo and Clementine missions now providing new global data sets of the Moon, it is imperative that the lunar science community synthesize these new data and integrate them with one another and with the lunar-sample database. Integrated approaches drawing upon multiple data sets can be used to address key problems of lunar origin, evolution, and resource definition and utilization. The idea to produce this Reviews in Mineralogy (RIM) volume was inspired by the realization that many types of planetary scientists and, for that matter, Earth scientists will need access to data on the planetary sample suite. Therefore, we have attempted to put together, under one cover, a comprehensive coverage of the mineralogy and petrology of planetary materials. The book is organized with an introductory chapter that introduces the reader to the nature of the planetary sample suite and provides some insights into the diverse environments from which they come. Chapter 2 on Interplanetary Dust Particles (IDPs) and Chapter 3 on Chondritic Meteorites deal with the most primitive and unevolved materials we have to work with. It is these materials that hold the clues to the nature of the solar nebula and the processes that led to the initial stages of planetary formation. Chapter 4, 5, and 6 consider samples from evolved asteroids, the Moon and Mars respectively. Chapter 7 is a brief summary chapter that compares aspects of melt-derived minerals from differing planetary environments.

Description / Table of Contents: This book is written with two goals in mind. The first is to derive the 32 crystallographic point groups, the 14 Bravais lattice types and the 230 crystallographic space group types. The second is to develop the mathematical tools necessary for these derivations in such a manner as to lay the mathematical foundation needed to solve numerous basic problems in crystallography and to avoid extraneous discourses. To demonstrate how these tools can be employed, a large number of examples are solved and problems are given. The book is, by and large, self-contained. In particular, topics usually omitted from the traditional courses in mathematics that are essential to the study of crystallography are discussed. For example, the techniques needed to work in vector spaces with noncartesian bases are developed. Unlike the traditional group-theoretical approach, isomorphism is not the essential ingredient in crystallographic classification schemes. Because alternative classification schemes must be used, the notions of equivalence relations and classes which are fundamental to such schemes are defined, discussed and illustrated. For example, we will find that the classification of the crystallographic space groups into the traditional 230 types is defined in terms of their matrix representations. Therefore, the derivation of these groups from the point groups will be conducted using the 37 distinct matrix groups rather than the 32 point groups they represent. We have been greatly influenced by two beautiful books. Hermann Heyl's book entitled Symmetry based on his lectures at Princeton University gives a wonderful development of the point groups as well as an elegant exposition of symmetry in art and nature. Fredrik W. H. Zachariasen's book entitled Theory of X-ray Diffraction in Crystals presents important insights on the derivation of the Bravais lattice types and the crystallographic space groups. These two books provided the basis for many of the ideas developed in this book. The theorems, examples, definitions and corollaries are labelled sequentially as a group whereas the problems are labelled separately as a group as are the equations. The manner in which these are labelled is self-explanatory. For example, T4.15 refers to Theorem (T) 15 in Chapter 4 while DAl.l refers to Definition (D) 1 in Appendix (A) 1. We have strived to write this book so that it is self-teaching. The reader is encouraged to attempt to solve the examples before appealing to the solution presented and to work all of the problems. Preface to the Revised Edition of Mathematical Crystallography In the Revised Edition we have corrected the errors, misprints and omissions that we have found and our students and other users have kindly pointed out to us. The Revised Edition also includes a more comprehensive index and a set of solutions for all of the problems presented in the book.

Description / Table of Contents: The first half-century of X-ray crystallography, beginning with the elucidation of the sodium chloride structure in 1914, was devoted principally to the determination of increasingly complex atomic topologies at ambient conditions. The pioneering work of the Braggs, Pauling, Wyckoff, Zachariasen and many other investigators revealed the structural details and underlying crystal chemical principles for most rock-forming minerals (see, for example, Crystallography in North America, edited by D. McLachlan and J. P. Glusker, NY, American Crystallographic Association, 1983). These studies laid the crystallographic foundation for modem mineralogy. The past three decades have seen a dramatic expansion of this traditional crystallographic role to the study of the relatively subtle variations of crystal structure as a function of temperature, pressure, or composition. Special sessions on "High temperature crystal chemistry" were first held at the Spring Meeting of the American Geophysical Union (April 19, 1972) and the Ninth International Congress of Crystallography (August 30, 1972). The Mineralogical Society of America subsequently published a special 11-paper section of American Mineralogist entitled "High Temperature Crystal Chemistry," which appeared as Volume 58, Numbers 5 and 6, Part I in July-August, 1973. The first complete three-dimensional structure refinements of minerals at high pressure were completed in the same year on calcite (Merrill and Bassett, Acta Crystallographica B31, 343-349, 1975) and on gillespite (Hazen and Burnham, American Mineralogist 59, 1166-1176, 1974). Rapid advances in the field of non-ambient crystallography prompted Hazen and Finger to prepare the monograph Comparative Crystal Chemistry: Temperature, Pressure, Composition and the Variation of Crystal Structure (New York: Wiley, 1982). At the time, only about 50 publications documenting the three-dimensional variation of crystal structures at high temperature or pressure had been published, though general crystal chemical trends were beginning to emerge. That work, though increasingly out of date, remained in print until recently as the only comprehensive overview of experimental techniques, data analysis, and results for this crystallographic sub-discipline. This Reviews in Mineralogy and Geochemistry volume was conceived as an updated version of Comparative Crystal Chemistry. A preliminary chapter outline was drafted at the Fall 1998 American Geophysical Union meeting in San Francisco by Ross Angel, Robert Downs, Larry Finger, Robert Hazen, Charles Prewitt and Nancy Ross. In a sense, this volume was seen as a "changing of the guard" in the study of crystal structures at high temperature and pressure. Larry Finger retired from the Geophysical Laboratory in July, 1999, at which time Robert Hazen had shifted his research focus to mineral-mediated organic synthesis. Many other scientists, including most of the authors in this volume, are now advancing the field by expanding the available range of temperature and pressure, increasing the precision and accuracy of structural refinements at non-ambient conditions, and studying ever more complex structures. The principal objective of this volume is to serve as a comprehensive introduction to the field of high-temperature and high-pressure crystal chemistry, both as a guide to the dramatically improved techniques and as a summary of the voluminous crystal chemical literature on minerals at high temperature and pressure. The book is largely tutorial in style and presentation, though a basic knowledge of X-ray crystallographic techniques and crystal chemical principles is assumed. The book is divided into three parts. Part I introduces crystal chemical considerations of special relevance to non-ambient crystallographic studies. Chapter 1 treats systematic trends in the variation of structural parameters, including bond distances, cation coordination, and order-disorder with temperature and pressure, while Chapter 2 considers P-V-T equation-of-state formulations relevant to x-ray structure data. Chapter 3 reviews the variation of thermal displacement parameters with temperature and pressure. Chapter 4 describes a method for producing revealing movies of structural variations with pressure, temperature or composition, and features a series of "flip-book" animations. These animations and other structural movies are also available as a supplement to this volume on the Mineralogical Society of America web site at RiMG041 Programs. Part II reviews the temperature- and pressure-variation of structures in major mineral groups. Chapter 5 presents crystal chemical systematics of high-pressure silicate structures with six-coordinated silicon. Subsequent chapters highlight temperature- and pressure variations of dense oxides (Chapter 6), orthosilicates (Chapter 7), pyroxenes and other chain silicates (Chapter 8), framework and other rigid-mode structures (Chapter 9), and carbonates (Chapter 10). Finally, the variation of hydrous phases and hydrogen bonding are reviewed in Chapter 11, while molecular solids are summarized in Chapter 12. Part III presents experimental techniques for high-temperature and high-pressure studies of single crystals (Chapters 13 and 14, respectively) and polycrystalline samples (Chapter 15). Special considerations relating to diffractometry on samples at non-ambient conditions are treated in Chapter 16. Tables in these chapters list sources for relevant hardware, including commercially available furnaces and diamond-anvil cells. Crystallographic software packages, including diffractometer operating systems, have been placed on the Mineralogical Society web site for this volume. This volume is not exhaustive and opportunities exist for additional publications that review and summarize research on other mineral groups. A significant literature on the high-temperature and high-pressure structural variation of sulfides, for example, is not covered here. Also missing from this compilation are references to a variety of studies of halides, layered oxide superconductors, metal alloys, and a number of unusual silicate structures.

Description / Table of Contents: The review chapters in this volume were the basis for a short course on molecular modeling theory jointly sponsored by the Geochemical Society (GS) and the Mineralogical Society of America (MSA) May 18-20, 2001 in Roanoke, Virginia which was held prior to the 2001 Goldschmidt Conference in nearby Hot Springs, Virginia. Dr. William C. Luth has had a long and distinguished career in research, education and in the government. He was a leader in experimental petrology and in training graduate students at Stanford University. His efforts at Sandia National Laboratory and at the Department of Energy's headquarters resulted in the initiation and long-term support of many of the cutting edge research projects whose results form the foundations of these short courses. Bill's broad interest in understanding fundamental geochemical processes and their applications to national problems is a continuous thread through both his university and government career. He retired in 1996, but his efforts to foster excellent basic research, and to promote the development of advanced analytical capabilities gave a unique focus to the basic research portfolio in Geosciences at the Department of Energy. He has been, and continues to be, a friend and mentor to many of us. It is appropriate to celebrate his career in education and government service with this series of courses in cutting-edge geochemistry that have particular focus on Department of Energy-related science, at a time when he can still enjoy the recognition of his contributions. Molecular modeling methods have become important tools in many areas of geochemical and mineralogical research. Theoretical methods describing atomistic and molecular-based processes are now commonplace in the geosciences literature and have helped in the interpretation of numerous experimental, spectroscopic, and field observations. Dramatic increases in computer power-involving personal computers, workstations, and massively parallel supercomputers-have helped to increase our knowledge of the fundamental processes in geochemistry and mineralogy. All researchers can now have access to the basic computer hardware and molecular modeling codes needed to evaluate these processes. The purpose of this volume of Reviews in Mineralogy and Geochemistry is to provide the student and professional with a general introduction to molecular modeling methods and a review of various applications of the theory to problems in the geosciences. Molecular mechanics methods that are reviewed include energy minimization, lattice dynamics, Monte Carlo methods, and molecular dynamics. Important concepts of quantum mechanics and electronic structure calculations, including both molecular orbital and density functional theories, are also presented. Applications cover a broad range of mineralogy and geochemistry topics-from atmospheric reactions to fluid-rock interactions to properties of mantle and core phases. Emphasis is placed on the comparison of molecular simulations with experimental data and the synergy that can be generated by using both approaches in tandem. We hope the content of this review volume will help the interested reader to quickly develop an appreciation for the fundamental theories behind the molecular modeling tools and to become aware of the limits in applying these state-of-the-art methods to solve geosciences problems.

Description / Table of Contents: Phase transformations occur in most types of materials, including ceramics, metals, polymers, diverse organic and inorganic compounds, minerals, and even crystalline viruses. They have been studied in almost all branches of science, but particularly in physics, chemistry, engineering, materials science and earth sciences. In some cases the objective has been to produce materials in which phase transformations are suppressed, to preserve the structural integrity of some engineering product, for example, while in other cases the objective is to maximise the effects of a transformation, so as to enhance properties such as superconductivity, for example. A long tradition of studying transformation processes in minerals has evolved from the need to understand the physical and thermodynamic properties of minerals in the bulk earth and in the natural environment at its surface. The processes of interest have included magnetism, ferroelasticity, ferroelectricity, atomic ordering, radiation damage, polymorphism, amorphisation and many others-in fact there are very few minerals which show no influence of transformation processes in the critical range of pressures and temperatures relevant to the earth. As in all other areas of science, an intense effort has been made to tum qualitative understanding into quantitative description and prediction via the simultaneous development of theory, experiments and simulations. In the last few years rather fast progress has been made in this context, largely through an interdisciplinary effort, and it seemed to us to be timely to produce a review volume for the benefit of the wider scientific community which summarises the current state of the art. The selection of transformation processes covered here is by no means comprehensive, but represents a coherent view of some of the most important processes which occur specifically in minerals.

Description / Table of Contents: Contents:Crystal Structure - Species - Crystallisation.- Crystal Chemistry of Clay Minerals.- Energy Balances.- Isotopic Composition of Clay Minerals.- Surface Properties.- Clays in Soils and Weathered Rocks.- Clays in Sedimentary Environments.- Diagenesis and Very Low-Grade Metamorphism.- Hydrothermal Process- Thermal Metamorphism.- Clays Under Extreme Conditions

Description / Table of Contents: Inhalt: 1 Tone und Tongesteine. - 2 Aufbau und Strukturprinzipien der silicatischen Tonminerale. - 3 Systematik der Tonmineralstrukturen. - 4 Tonmineralneubildung und ihre Voraussetzungen. - 5 Spezielle Tonmineralogie. - 6 Spezielle Eigenschaften der silicatischen Tonkomponenten. - 7 Tonminerale in einer anthropogen veränderten Umwelt. - 8 Hinweise zur mineralogischen Untersuchung von Tongesteinen. - Anhang: Zusammensetzung und Eigenschaften wichtiger Tonminerale. - Anmerkungen. - Literatur. - Sachregister

Description / Table of Contents: Die Tonminerale gehören u. a. wegen ihrer hohen Reaktionsempfindlichkeit gegenüber Milieuveränderungen zu den eigentümlichsten Erscheinungen unserer anorganischen Welt. Sie nehmen in einigen Bereichen der gegenwärtigen Umweltproblematik geradezu (nicht immer klar erkannte) Schlüsselpositionen ein - so z. B. bei den Waldschäden. So wurde in diesem Buch versucht, nach einleitenden Betrachtungen zur Verbreitung und Genese von Tongesteinen und neben einer zusammenfassenden Darstellung der heutigen Tonmineralogie, vor allem das Verhalten der Tone und Tonminerale durch Ableitung von ihren Struktureigenschaften auch einem breiteren Interessentenkreis verständlich zu machen.

Description / Table of Contents: The development of modern isotope geochemistry is without doubt attributed to the efforts, begun in the 1930's and 1940's, of Harold Urey (Columbia University and the University of Chicago) and Alfred O.C. Nier (University of Minnesota). Urey provided the ideas, theoretical foundation, the drive, and the enthusiasm, but none of this would have made a major impact on Earth Sciences without the marvelous instrument developed by Nier and later modified and improved upon by Urey, Epstein, McKinney, and McCrea at the University of Chicago. Harold Urey's interest in isotope chemistry goes back to the late 1920's when he and I.I. Rabi returned from Europe and established themselves at Columbia to introduce the then brand-new concepts of quantum mechanics to students in the United States. Urey, of course, rapidly made an impact with his discovery of deuterium in 1932, the 'magical' year in which the neutron and positron were also discovered. Urey followed up his initial important discovery with many other experimental and theoretical contributions to isotope chemistry. During this period, Al Nier developed the most sophisticated mass spectrometer then available anywhere in the world, and made a series of surveys of the isotopic ratios of as many elements as he could. Through these studies, which were carried out mainly to obtain accurate atomic weights of the various elements, Nier and his co-workers clearly demonstrated that there were some fairly large variations in the isotopic ratios of the lighter elements. However, the first inkling of a true application to the Earth Sciences didn't come until 1946 when Urey presented his Royal Society of London lecture on 'The Thermodynamic Properties of Isotopic Substances' (now a classic paper referenced in most of the published papers on stable isotope geochemistry). With the information discovered by Nier and his co-workers that limestones were about 3 percent richer in 18O than ocean water, and with his calculations of the temperature coefficient for the isotope exchange reaction between CaCO3 and H2O, Urey realized that it might be possible to apply these concepts to determining the paleotemperatures of the oceans. Urey was never one to overlook important scientific problems, regardless of the field of scientific inquiry involved. In fact, he always admonished his students to 'work only on truly important problems!' Urey, then a Professor at the University of Chicago, decided to take a hard look into the experimental problems of developing an oxygen isotope paleotemperature scale. Although the necessary accuracy had not yet been attained, the design of the Nier instrument seemed to offer a good possibility, with suitable modifications, of making the kinds of precise measurements necessary for a sufficiently accurate determination of the 18O/16O ratios of both CaCO3 (limestone) and ocean water. Enormous efforts would be required to do this, because even if all the mass spectrometric problems could be solved, every analytical and experimental procedure would have to be invented from scratch, including the experimental calibration of the temperature coefficient of the equilibrium fractionation factor between calcite and water at low temperatures. To carry out this formidable study, Urey gathered around himself a remarkable group of students, postdoctoral fellows, and technicians, as well as his paleontologist colleague Heinz Lowenstam. With Sam Epstein at the center of the effort and acting as the principal driving force, the rest, as they say, 'is history.' The marvelous nature of the Nier-Urey mass spectrometer is attested to by the fact that the basic design is still being used, and that there are now hundreds of laboratories throughout the world where this kind of work is being done. For example, the original instrument built by Sam Epstein and Chuck McKinney at Caltech in 1953 is still in use and has to date produced more than 90,000 analyses. University, government, and industrial laboratories have found these instruments to be an indispensable tool. Enormous and widely varying application of the original concepts have been made throughout the whole panoply of Earth, Atmospheric, and Planetary Sciences. In the present volume we concentrate on an important sub-field of this effort. That particular sub-field was inaugurated in Urey's laboratories at Chicago by Peter Baertschi and Sol Silverman, who developed the fluorination technique for extracting oxygen from silicate rocks and minerals. This technique was later refined and improved in the late 1950's by Sam Epstein, Hugh Taylor, Bob Clayton, and Toshiko Mayeda, and has become the prime analytical method for studying the oxygen isotope composition of rocks and minerals. The original concepts and potentialities of high-temperature oxygen isotope geochemistry were developed by Samuel Epstein and his first student, Bob Clayton. Also, Bob Clayton, A.E.J. Engel, and Sam Epstein carried out the first application of these techniques to the study of ore deposits. The first useful experimental calibrations of the high-temperature oxygen isotope geothermometers quartz-calcite-magnetite-H2O were carried out initially by Bob Clayton, and later with his first student Jim O'Neil. In the meantime, Sam Epstein and his second student, Hugh Taylor, had begun a systematic study of 18O/16O variations in igneous and metamorphic rocks, and were the first to point out the regular order of 18O/16O fractionations among coexisting minerals, as well as their potential use as geochemical tracers of petrologic processes. During this period, a parallel development of sulfur isotope geochemistry was being carried out by Harry Thode and his group at McMaster University in Canada. They developed all the mass spectrometric and extraction techniques for this element, and also provided the theoretical and experimental foundation for understanding the equilibrium and kinetic isotope chemistry of sulfur. Starting from these beginnings, most of which took place either at the University of Chicago, Caltech, or McMaster University (but also with important input from Irving Friedman's laboratory at the U.S. Geological Survey, from Athol Rafter's laboratory in New Zealand, and from Columbia, Penn State, and the Vernadsky Institute in Moscow), there followed during the decades of the late 60's, 70's, and early 80's the development and maturing of the sub-field of high-temperature stable isotope geochemistry. This discipline is now recognized as an indispensable adjunct to all studies of igneous and metamorphic rocks and meteorites, particularly in cases where fluid-rock interactions are a major focus of the study. The twin sciences of ore deposits and the study of hydrothermal systems, both largely concerned with such fluid-rock interactions, have been profoundly and completely transformed. Virtually no issue of Economic Geology now appears without 3 or 4 papers dealing with stable isotope variations. No one writes papers on the development of the hydrosphere, hydrothermal alteration, ore deposits, melt-fluid-solid interactions, etc. without taking into account the ideas and concepts of stable isotope geochemistry. Although the present volume represents only a first effort to fill the need for a general survey of this sub-field for students and for workers in other disciplines, and although it is still obviously not completely comprehensive, it should give the interested student an idea of the present 'state-of-the-art' in the field. It should also provide an entry into the pertinent literature, as well as some understanding of the basic concepts and potential applications. Some thought went into the arrangement and choice of chapters for this volume. The first three chapters focus on the theory and experimental data base for equilibrium, disequilibrium, and kinetics of stable isotope exchange reactions among geologically important minerals and fluids. The fourth chapter discusses the primordial oxygen isotope variations in the solar system prior to formation of the Earth, along with a discussion of isotopic anomalies in meteorites. The fifth chapter discusses isotopic variations in the Earth's mantle and the sixth chapter reviews the variations in the isotopic compositions of natural waters on our planet. In Chapters 7, 8, 9 and 10, these isotopic constraints and concepts are applied to various facets of the origin and evolution of igneous rocks, bringing in much material on radiogenic isotopes as well, because these problems require a multi-dimensional attack for their solution. In Chapters 11 and 12, the problems of hydrothermal alteration by meteoric waters and ocean water are considered, together with discussions of the physics and chemistry of hydrothermal systems and the 18O/16O history of ocean water. Finally, in Chapters 13 and 14, these concepts are applied to problems of metamorphic petrology and ore deposits, particularly with respect to the origins of the fluids involved in those processes. It seems clear to us (the editors) that this sub-field of stable isotope geochemistry can only grow and become even more pertinent and dominant in the future. One of the most fruitful areas to pursue is the development of microanalytical techniques so that isotopic analyses can be accurately determined on ever smaller and smaller samples. Such techniques would open up vast new territories for exploitation in every aspect of stable isotope geochemistry. Exciting new methods have recently been developed whereby a few micromoles of CO2 and SO2 can be liberated for isotopic analyses from polished sections of carbonates and sulfides by laser impact. There are also new developments in mass spectrometry like RIMS (resonance ionization mass spectrometry), Fourier transform mass spectrometry and the ion microprobe that offer considerable promise for these purposes. Stable isotope analyses of large-sized samples (even those that must be obtained by reactions of silicates with fluorinating reagents) have now become so routine and so rapid that they represent an 'easy' way to gather a lot of data in a hurry. In fact 'mass production' techniques for rapidly processing samples are starting to become prevalent, so much so that one of the biggest worries in the future may be that a flood of data will overwhelm us and outstrip our abilities to carefully define and carry out sampling strategies, as well as to think carefully and in depth about the data. An organized system of handling the D/H, 13C/12C, 15N/14N, 18O/16O, and 34S/32S data, and/or a computerized data base that could be manipulated and added to would be a useful path to follow in the future, particularly if it were integrated into a larger data base containing radiogenic isotope data, major- and trace-element analyses, electron microprobe data, x-ray crystallographic data, and petrographic data (particularly modal data on mineral abundances in the rocks).

Description / Table of Contents: The Mineralogical Society of America (MSA) sponsored a short course by this title December 1990 at the Cathedral Hill Hotel in San Francisco, California. It was organized by the editors, Jim Nicholls and Kelly Russell, and presented by the authors of this volume to about 80 participants in conjunction with the Fall Meeting of the American Geophysical Union. Igneous petrology, in its broadest applications, treats the transfer of matter and energy from planetary interiors to their exteriors. Over the past several decades igneous petrology has gained sophistication in three areas that deal with such transfers: the properties of silicate melts and solids can be estimated as functions of pressure, temperature and composition; some results of experimental and theoretical studies of the physics of multiphase flow are available; and many of the algorithms for realistically modeling magmatic processes are in place. Each of these fields of study, to some extent, have to be pursued independently. In our opinion, now is an ideal time to collect some features of these studies as preparation for more integrated future work and to show some consequences of applying current ideas to the study of igneous processes. We have attempted to bring together the basic data and fundamental theoretical constraints on magmatic processes with applications to specific problems in igneous petrology.

Description / Table of Contents: This volume of was prepared in conjunction with the Mineralogical Society of America Short Course on Amphiboles and Other Hydrous Pyriboles, Fall, 1981. Had it not been split into two volumes, 9A and 9B, it would have resembled in some respects the Manhattan telephone directory (it is hoped, however, that the content is more readable and relevant to the geological sciences). The length of this collection of papers appears to result from a combination of phenomena. The amphiboles themselves must accept most of the blame: their structural complexity and resulting chemical variability and diversity of petrologic behavior preclude brief description. In addition, while some of these papers are relatively brief summaries of the published literature that easily and quickly can be consumed by students, others are exhaustive (and lengthy) discourses that may not be digestible in one sitting by even the most dedicated amphibole researcher. Finally, it appears that some geologists, probably with justification, love amphiboles so much that they would never have stopped writing had there been no publication deadline. The extremely short time between the preparation of papers and publication of Reviews in Mineralogy and the authors' intimate knowledge of their fields ensure that the papers reflect the very latest in research results. The rapid production of the "Reviews," however, inevitably results in a few errors that might be caught in a more leisurely publication process; the editors apologize for any such errors that are included in this volume. In addition, the sequence of presentation of papers reflects not only the editors' notions of order in the amphibole universe, but also somewhat the order in which papers were received. Although a collection of reviews of this sort cannot claim to give exhaustive coverage to all aspects of a topic, it is hoped that the papers presented here do review most of the important areas of active amphibole research. The papers have been split in a somewhat arbitrary fashion into Volume 9A, Amphiboles and Other Hydrous Pyriboles - Mineralogy, and Volume 9B, Amphiboles: Petrology and Experimental Phase Relations. Everyone is encouraged to purchase both volumes, however, because there is a hefty dose of petrology in 9A (witness the paper by Thompson, for example) and not a little mineralogy in 9B.

Description / Table of Contents: This volume of Reviews in Mineralogy attempts to synthesize our present understanding of certain aspects of the mineralogy and chemistry of the rock-forming carbonates. Hopefully, it reflects the presently more active areas of research. This review follows, by ten years, a major assessment of (sedimentary) carbonate minerals by Lippmann (1973). There is only minor overlap of subject material, and I hope that this difference reflects fairly how this field has developed. In some respects carbonates are unique, for they are one of the few mineral groups providing an abundant record of biological, physical, and chemical processes throughout much of geologic time. Because of their relative importance in sedimentary rocks, lowtemperature examples are given more emphasis here. Moreover, the obvious correlation with energy resources has been a significant factor contributing to the current resurgence of interest in this area. However, the broader interest in carbonates is also a reflection of their widespread occurrence in vastly different geologic environments, including metamorphic and igneous settings, as well as an appreciation of their role in both atmospheric and oceanic chemistry, both past and present. In this volume, some of the papers are general (i.e., those addressing crystal chemistry and phase relations), and they provide overviews of a fundamental nature and are of interest to many. Others are more specialized in coverage and generally reflect the different approaches used in carbonate geochemistry. The final chapter introduces transmission electron microscopy, a relatively new and powerful technique for mineralogical research that has great potential in carbonate research. Owing to the short time interval between the completion of manuscripts and publication, much of the newer material in this volume is still "fresh." The various reviewers, all gratefully acknowledged, were expeditious in their efforts. A hurried schedule, however, allows for unnoticed errors to persist; these should be brought to my attention. PREFACE TO THE SECOND PRINTING Interest in carbonate research has continued at an ever-hurried pace since this book was first printed. While the individual chapters could not be revised in this second printing to include the many new findings, a partial listing of noteworthy papers that have since appeared are given in an Appendix at the end of the volume (p. 395-399). These papers are arranged by chapters corresponding roughly to the subject area discussed. In addition, incomplete references from the first printing are listed in this appendix. The assistance of the authors and especially of Paul Ribbe is greatly appreciated.

Description / Table of Contents: This is a book exclusively devoted to three minerals: the Al2SiO5 polymorphs - andalusite, sillimanite, and kyanite. This may seem to be narrowly focused and esoteric. However, as discussed in Chapter 1, the aluminum silicate polymorphs are perhaps the most important mineral group to metamorphic petrologists. Because these minerals occur in anatectic migmatites and peraluminous granitoids, they are also important in igneous petrology. In spite of their geologic significance, there are a variety of experimental, theoretical, and field problems involving the aluminum silicates. Theoretical problems include the nature and energetics of lattice defects, order/disorder, crystalline (solid) solution, and interfacial energy. The aluminum silicates epitomize the importance of understanding the mechanisms and kinetics of heterogeneous metamorphic reactions. The difficulties in calibration of the pressure-temperature (P- T) phase equilibrium diagram illustrate the pitfalls of hydrothermal experimentation and the need to understand the methodology and uncertainties of calorimetric measurements of thermodynamic data of minerals. Thus, this book covers a wide variety of topics that must be considered in the analysis of metamorphic systems. In so doing, this volume illustrates the fact that modern metamorphic petrology demands an awareness of a wide spectrum of geologic variables and processes. In concert with the tenor of the Mineralogical Society of America Reviews in Mineralogy series, this volume is intended to provide a comprehensive review, summarizing the methods, theories and pitfalls of the various contributions on the aluminum silicates. Hopefully, this book will provide readers with a reasonably in-depth overview, and thus avoid the need for extensive, independent literature reviews. Although a concerted effort was made to give a balanced coverage of divergent theories regarding various problems involving the aluminum silicates, this critique nevertheless includes some of the author's biases. Several sections of this book present the chronological development of research on various topics, giving readers historical perspectives on the development of theories, models and biases on various problems regarding the aluminum silicates. As in all fields, several landmark studies have set the tone for the strategy of approach to problems. Although such studies have provided important steps forward in our understanding of natural phenomena, they have had the undesirable effect of entrenching biases and methodology. In this volume I have attempted to point out the deleterious effects of certain parochial approaches, an example being the aluminum immobility concept discussed in Chapter 10. In addition to their primary importance in metamorphic petrology, the aluminum silicates illustrate a wide variety of experimental, theoretical, and experimental problems. Because the Al2SiO5 polymorphs alone offer a pedagogic illustration of many important principles of modern metamorphic petrology.

Description / Table of Contents: This volume was published to be used as the textbook for the Short Course on Fe-Ti Oxides: Their Petrologic and Magnetic Significance, held May 24-27, 1991, organized by B.R. Frost, D.H. Lindsley, and SK Banerjee and jointly sponsored by the Mineralogical Society of America and the American Geophysical Union. It has been fourteen and a half years since the last MSA Short Course on Oxide Minerals and the appearance of Volume 3 of Reviews in Mineralogy. Much progress has been made in the interim. This is particularly evident in the coverage of the thermodynamic properties of oxide minerals: nothing in Volume 3, while in contrast, Volume 25 has three chapters (6, 7, and 8) presenting various aspects of the thermodynamics of oxide minerals; and other chapters (9, 11, 12) build extensively on thermodynamic models. The coverage of magnetic properties has also been considerably expanded (Chapters 4, 8, and 14). Finally, the interaction of oxides and silicates is emphasized in Chapters 9, 11, 12, 13, and 14. One of the prime benefits of Reviews in Mineralogy has been that any scientist can afford to have it at his or her fingertips. Because Volume 3 is out of print and will not be readily available to newcomers to our science, as much as possible we have tried to make Volume 25 a replacement for, rather than a supplement to, the earlier volume. Chapters on crystal chemistry, phase equilibria, and oxide minerals in both igneous and metamorphic rocks have been rewritten or extensively revised. The well received photographs of oxide textures in Volume 3 have been collected and expanded into a "Mini-Atlas" In Volume 25. Topics that receive less attention than in the earlier volume are oxides in lunar rocks and meteorites, and the manganese minerals. We hope that the new volume will tum out to be as useful as the previous one was.

Description / Table of Contents: The Mineralogical Society of America sponsored a short course on Contact Metamorphism, October 17-19, 1991, at the Pala Mesa Resort, Fallbrook, California, prior to its annual meeting with the Geological Society of America. As reviewed in Chapter 1, contact aureoles have unique attributes for elucidating the processes and controls of metamorphism. Within the last two decades there has been considerable evolution in our knowledge of metamorphism. This evolution spans a wide range of scales from submicroscopic analysis of grain boundaries through to regional scale analysis of contact metamorphism associated with batholith terrains. Geological sciences is becoming increasingly multidisciplinary in nature. Traditionally, contact aureoles were primarily studied by metamorphic petrologists. Their mapping of isograds and mineral zones in aureoles, coupled with microscopic analysis of the prograde metamorphic evolution of textures, structures and mineralogy, has provided an excellent framework for our understanding of contact metamorphism. However, complete understanding of the processes and controls of contact metamorphism requires a multidisciplinary analysis from a wide range of geological subdisciplines. This volume provides a multidisciplinary review of our current knowledge of contact metamorphism. As in any field of endeavor, we are provided with new questions, thereby dictating future directions of study. Hopefully, this volume will provide inspiration and direction for future research on contact metamorphism.

Description / Table of Contents: Fourteen years ago the American Geological Institute (AGI) sponsored a Short Course on Chain Silicates. At that time, a substantial amount was known about the crystal chemistry and phase equilibria of pyroxenes, and this knowledge has been of fundamental importance in guiding research on pyroxenes in the years following the AGI Short Course. In 1966, single-crystal x-ray diffractometry was well advanced and good crystal structure refinements were available for jadeite, spodumene, hypersthene, c1inoferrosi1ite, orthoferrosi1ite, and omphacite; the distinction between the c1inoenstatite (pigeonite) and diopside (augite) structures had been established, and the structure of protoenstatite was known, although some doubt existed about the space group of protoenstatite. Phase diagrams for several joins in the pyroxene quadrilateral had been published, but often equilibrium had not been established in the experiments and not enough was known about the effects of pressure, oxygen fugacity, and non-quad elements such as aluminum on the phase equilibria. Also, inversion relations of Ca-poor pyroxenes were not well understood, and petrologists had just become aware of the effect of stress on orthoto-clinopyroxene transitions. In 1966 few of us would have guessed how-much new data and new analytical results would become available in the next fourteen years. Although most, if not all, of the important instrumental techniques we use today were available in 1966, the truly spectacular development and application of these techniques did not take place until the Apollo 11 samples and the attendant funding from NASA became available. Pyroxene research has profited immensely from the application of Mossbauer, optical, and infrared spectroscopy, x-ray and electron diffraction, transmission electron microscopy, automated electron microprobes, and digital computers. During these years experimentalists extended the capabilities of their equipment to examine the behavior of pyroxenes under conditions of controlled oxygen fugacity, pressure, and temperature, conditions more nearly like those under which pyroxenes crystallize in natural systems. Looking back, one remembers the excitement of seeing the first lunar samples. We were surprised at the large amounts of pigeonite and the quality of crystals unaffected by water or the presence of sodium. The influence of the lunar program on pyroxene research was extraordinary, and our understanding of pyroxene relationships in terrestrial occurrences benefited tremendously because the lunar pyroxenes provided a basis for comparison with the more complex chemical and structural behavior of terrestrial environments. Probably the most impressive development in the early lunar sample studies was the application of transmission electron microscopy to mineralogy. We were able to see exsolution and other textural features in crystals that looked homogeneous in the optical microscope, thus opening up a wide range of research possibilities that had not existed previously. Advanced crystal growth experiments, detailed phase equilibria, x-ray diffraction at high temperatures, and statistical analyses of microprobe data were all applied to lunar pyroxenes and then extended to terrestrial and meteorite investigations, making this period one of the most productive in history. In the compilation of this volume, an attempt has been made to review the essential aspects of pyroxene research, primarily those of the last ten or fifteen years. Although the largest fraction of pyroxene research has been performed in the U.S.A., significant advances have been made in other countries, particularly in Europe, Japan, Canada, and Australia, with interest and activity in these countries probably growing at a faster rate than in the United States. Recently, Deer, Howie and Zussman (DHZ) published a second edition of their volume in the Rock-Forming Minerals series, Single-Chain Silicates, Vol. 2A (John Wiley, New York, 1978). The present volume is intended to be complementary to DHZ and to provide material covered lightly or not at all in DHZ, such as electron microscopy, spectroscopy, and detailed thermodynamic treatments. However, because the range of pyroxene research has grown so much in recent years, there still are important areas not covered comprehensively in either of these volumes. Some of these areas are kinetics, diffusion, crystal defects, deformation, and nonsilicate pyroxene crystal chemistry. Because of these omissions and because this volume is intended for use with the MSA Short Course on Pyroxenes to be held at Emory University in conjunction with the November, 1980 meeting of the Society, a Symposium on Pyroxenes was organized by J. Stephen Huebner for the meeting that is designed to present the latest research results on several different topics, including those above. With DHZ, this volume, and publications from the Symposium, the student of pyroxenes should be well-equipped to advance our knowledge of pyroxenes in the decades ahead.

Description / Table of Contents: In 1978 the Short Course Committee decided to forego activities because the annual meeting of the M.S.A. was held together with the Mineralogical Association of Canada, who sponsored a Short Course in Uranium Deposits and published a book by the same title. A number of mineralogists expressed regret at the potential loss of momentum in MSA's production of this series and encouraged several authors of this book to press on with their idea of publishing Volume 5 -- Orthosilicates. Work was begun in 1978; however, without the pressure of a deadline associated with presenting the material to students of a short course at the annual meeting, procrastination set in and the first edition of this volume was not completed until September 1980 (with the exception of Chapters 1 and 2 which were submitted in their present form in 1978). In the meantime Volume 6, Marine Minerals, appeared in time for the annual meeting of the Society and a Short Course in San Diego in November 1979. In 1980 the Council of the MSA changed the name of the published volumes from SHORT COURSE NOTES to REVIEWS in MINERALOGY in order to more aptly describe the material contained in this now highly successful series. The First Edition of Orthosilicates was the first volume to appear under the REVIEWS banner. This is the Second Edition of Orthosilicates. It contains an updating and minor revisions of Chapters 3 through 10 (only) and two new chapters originally intended for the First Edition. The intent of this volume is to emphasize the crystal chemistry and related physical properties of the major rock-forming orthosilicates. Though in some chapters more attention is given to phase equilibria and paragenesis than in others, these are for the most part cursorily treated with references to the more important papers and to review articles (also see Deer, Howie and Zussman, 1962, Rock-forming Minerals, Vol. 1, Ortho- and Ring Silicates). Some confusion will inevitably result from the definition of the term used as the title for this volume. In Chapter 1 Liebau (p. 14) says that "silicates containing (SiO4) groups should be called monosilicates rather than orthosilicates or nesosilicates." The editor chose not to adopt Liebau's terminology for the title, because monosilicate is not yet widely accepted (although it might well be). To set manageable boundaries for the scope of the First Edition of Orthosilicates, an editorial option was exercised in rejecting as "orthosilicates" those minerals with both (SiO4) tetrahedra and (Si2O7) groups (zoisite, epidote, vesuvianite, etc.), as well as those with (SiO4) tetrahedra that are polymerized to other tetrahedra by sharing corners with (BeO4), (BO4), (A1O4), (ZnO4), etc. However, as mentioned in the Foreword, Chapter 13 has been added to the Second Edition to correct for the latter omission. Chapter 12 contains very brief descriptions of the paragenesis and crystal chemistry of many orthosilicates that fit the description stated in the Preface (p. iv). It may be used as an index, because all orthosilicates are listed alphabetically, including those discussed in Chapters 2 through 11.