THE proliferation and the importance of the results of crystal structure analysis confront the chemist with the need to learn the language of crystallography. This book is an outgrowth of the opinion that the training of the undergraduate chemistry major can include more of this language than the memorization of a list of lattice types. At the same time, it would be unreasonable and impractical to expect all chemists to become experts in this specialized field. The purpose, therefore, is to treat the subject in a manner that will quickly and painlessly enable the nonspecialist to read and comprehend the crystallographic literature. It is hoped that this introduction may serve as a useful starting point for those students who wish to pursue the subject further.

The principal message is contained in the first four chapters. That is, these chapters supply the vocabulary of crystallography, and descriptions of crystal structures should be rendered intelligible by acquaintance with this language. In order not to discourage the general reader, the use of mathematics has been kept to a minimum. The decision to omit vector and matrix methods was made reluctantly, in order to reduce the prerequisites, but the elegance thus sacrificed is a luxury that some exceptionally competent crystallographers get along without

Almost every human endeavor is influenced by minerals. Many natural resources used in the manufacture of goods on which civilization and our lives depend begin as minerals in the ground. The crops that we eat are grown in soil composed of minerals. The safety and stability of structures such as buildings, roads, and bridges depend on the mechanical properties of the minerals that make up the rocks and soil on which they are built. In addition, the chemical composition, structure, and texture of the minerals that compose the rocks beneath our feet provide myriad clues that guide geoscientists as they attempt to decipher the history of the earth.

Since time immemorial the minerals, rocks and soil had been the major attraction for the growth, development, and survival of every living entity including human, animals, birds, plants, and trees. That indeed forced us to know more about the minerals (mineralogy) and the rocks and soils (petrology).

This book is intended for use in an introductory optical mineralogy course. The objective in preparing the book was to present in a single volume of reasonable size both a thorough treatment of optical theory as it pertains to mineral identification with the petrographic microscope, and detailed mineral descriptions of the common rock-forming minerais. The first seven chapters <leal with optical theory and provide an introduction to the properties oflight, a description of the petrographic microscope, and a discussion of the optical properties of isotropic and anisotropic materiais. Detailed step-by-step procedures have been included to guide students through the measurement of optical properties in both thin section and grain mount. Selected spindle stage techniques also are included. <...>