This is an ideal textbook for both advanced undergraduates and graduate students. It contains valuable coverage of the optical properties of minerals, as well as up-to-date descriptions of common rock-forming minerals. The chapters on optical theory include discussions of the nature and properties of light, the petrographic microscope, and the behavior of light in isotropic materials and in uniaxial and biaxial anisotropic materials. Thoroughly revised to include recent developments in the field, the book includes step-by-step procedures to guide students through the determination of all optical properties by which minerals are routinely identified with a petrographic microscope. Readers will find descriptive information on over 125 common rock forming minerals, and many photomicrographs and illustrations. The book also includes a flow sheet to guide students through the process of identifying an unknown mineral.