Chemical principles are fundamental to the Earth sciences, and geoscience students increasingly require a firm grasp of basic chemistry to succeed in their studies. The enlarged third edition of this highly regarded textbook introduces the student to such 'geo-relevant' chemistry, presented in the same lucid and accessible style as earlier editions, but the new edition has been strengthened in its coverage of environmental geoscience and incorporates a new chapter introducing isotope geochemistry. The book comprises three broad sections. The first (Chapters 1-4) deals with the basic physical chemistry of geological processes. The second (Chapters 5-8) introduces the wave-mechanical view of the atom and explains the various types of chemical bonding that give Earth  materials their diverse and distinctive properties. The final chapters (9-11) survey the geologically relevant elements and isotopes, and explain their formation and their abundances in the cosmos and the Earth. The book concludes with an extensive glossary of terms; appendices cover basic maths, explain basic solution chemistry, and list the chemical elements and the symbols, units and constants used in the book.