This crystal book is a must have for those who use cyrstals in a healing practice or just have them around the home or office for protection, cleansing, or prosperity, etc. Cassandra clearly and thoroughly introduces the basics and more of using crystals as they apply to the chakra system, the aura, psychic development, pendulum dowsing, etc. Everything you need to know about the world of crystals is in this book! She explains 150 different crystals for healing, environment, children, history of, divinatory significance, uses at work and home and more! Each crystal description is accompanied by a clear, color picture for identification purposes. The book is sectioned by color of the stone which makes finding information on a particular stone easy. You need to know only the color of a stone and if you do not know the color the easy to read index in the back of the book is complete. I highly recommend this book to beginners and advanced healers alike. As a reference book it is invaluable!