Geochemistry is the science that uses the tools and principles of chemistry to explain the mechanisms behind major geological systems such as the Earths crust and its oceans. The realm of geochemistry extends beyond the Earth, encompassing the entire Solar System and has made important contributions to the understanding of a number of processes including mantle convection, the formation of planets and the origins of granite and basalt. Geochemistry for undergraduate/graduate students with at least an elementary-level background in earth sciences, chemistry, and mathematics. In keeping with the modern trend in the field of geochemistry, the book emphasizes computational techniques by developing appropriate mathematical relations, solving a variety of problems to illustrate application of the mathematical relations, and leaving a set of questions at the end of each chapter to be solved by students.