You can throw away those rock and mineral guides you've been collecting through the years; this well-written and well-thought out guide makes them pale and obsolete. I bought this for myself, then needed another one for a young niece who was captivated by its straightforward style and unbelievable photos. It is clean and organized and easy to use as a reference. It would also make a great text for self-education as it places rocks and minerals in context, including photos and descriptions of famous cliffs, sills, and other geologic formations around the world.