Reseña del editor An introduction to all aspects of the descriptive study of igneous and metamorphic rocks.Introduction. 1. Review of the Microscope and Mineral Optics. 2. Rock-Forming Minerals and Their Optical Properties. 3. Classification of Igneous Rocks. 4. Texture and Structures of Igneous Rocks. 5. Classification and Textures of Metamorphic Rocks. Index.