tourmaline, gems

A comprehensive synthesis of tourmaline mineralogy and gemology, drawing on more than 2,500 publications and incorporating nearly 1,000 references. Dietrich examines nomenclature, crystal morphology and structure, chemical composition, and the relationships between chemistry, species classification, and physical properties. Coverage includes crystal habits, exceptionally large crystals, inclusions and intergrowths, causes of color, color patterns, pleochroism, luminescence, and the effects of heating and irradiation. Additional chapters address physical properties, laboratory synthesis, industrial applications, and recovery. The gemstone chapter discusses tourmaline’s historical use in jewelry and decorative arts, fashioning, and notable gems. Geological coverage considers occurrences and formation in igneous, metamorphic, and sedimentary environments, while an appendix lists important sources of mineral specimens and gem material worldwide. The work’s principal strength is its organized compilation and evaluation of a widely scattered literature, making it useful to mineralogists, gemologists, and collectors. Individual deposits receive limited treatment, however, and the locality appendix lacks references directing readers to detailed accounts.