Description

Several years ago, John Rakovan and John Hughes (colleagues at Miami of Ohio), and later Matt Kohn (at South Carolina), separately proposed short courses on phosphate minerals to the Council of the Mineralogical Society of America (MSA). Council suggested that they join forces. Thus this volume, Phosphates: Geochemical, Geobiological, and Materials Importance, was organized. It was prepared in advance of a short course of the same title, sponsored by MSA and presented at Golden, Colorado, October 25-27.

We are pleased to present this volume entitled Phosphates: Geochemical, Geobiological and Materials Importance. Phosphate minerals are an integral component of geological and biological systems. They are found in virtually all rocks, are the major structural component of vertebrates, and when dissolved are critical for biological activity. This volume represents the work of many authors whose research illustrates how the unique chemical and physical behavior of phosphate minerals permits a wide range of applications that encompasses phosphate mineralogy, petrology, biomineralization, geochronology, and materials science. While diverse, these fields are all linked structurally, crystal-chemically and geochemically. As geoscientists turn their attention to the intersection of the biological, geological, and material science realms, there is no group of compounds more germane than the phosphates.

The chapters of this book are grouped into five topics: Mineralogy and Crystal Chemistry, Petrology, Biomineralization, Geochronology, and Materials Applications.

• In the first section, three chapters are devoted to mineralogical aspects of apatite, a phase with both inorganic and organic origins, the most abundant phosphate mineral on earth, and the main mineral phase in the human body. Monazite and xenotime are highlighted in a fourth chapter, which includes their potential use as solid-state radioactive waste repositories. The Mineralogy and Crystal Chemistry section concludes with a detailed examination of the crystal chemistry of 244 other naturally-occurring phosphate phases and a listing of an additional 126 minerals.

• In the Petrology section, three chapters detail the igneous, metamorphic, and sedimentary aspects of phosphate minerals. A fourth chapter provides a close look at analyzing phosphates for major, minor, and trace elements using the electron microprobe. A final chapter treats the global geochemical cycling of phosphate, a topic of intense, current geochemical interest.
• The Biomineralization section begins with a summary of the current state of research on bone, dentin and enamel phosphates, a topic that crosses disciplines that include mineralogical, medical, and dental research. The following two chapters treat the stable isotope and trace element compositions of modern and fossil biogenic phosphates, with applications to paleontology, paleoclimatology, and paleoecology.
• The Geochronology section focuses principally on apatite and monazite for U-ThPb, (U- Th)/He, and fission-track age determinations; it covers both classical geochronologic techniques as well as recent developments.
• The final section-Materials Applications-highlights how phosphate phases play key roles in fields such as optics, luminescence, medical engineering and prosthetics, and engineering of radionuclide repositories. These chapters provide a glimpse of the use of natural phases in engineering and biomedical applications and illustrate fruitful areas of future research in geochemical, geobiological and materials science. We hope all chapters in this volume encourage researchers to expand their work on all aspects of natural and synthetic phosphate compounds.

Matthew L. Kohn. Columbia, South Carolina, USA
John Rakovan and John M. Hughes, Oxford, Ohio, USA
August 17, 2002