One of Cunningham's least fluffy and most useful encyclopedic works. Despite frequent use of terms such as 'empowerment,' 'vibrations,' 'visualization', and other new-agey statements, the work itself is a solid reference and manual.
Chapters on stone energies, color and form magic, obtaining and cleansing stones, form a good grounding for the user. A meditation chapter, 'The Stories Within Stones' is perhaps the best part of the book, leading the user to become attuned with the stones he/she is using. Divination methods are covered, along with a 'stone tarot', which is a reasonable construct, though the concept seems a bit silly and Cunningham's renaming of 'Christian-influenced' cards is a bit random -- 'The Chariot' becomes 'The Elements'. The magic of jewelry and basic spells for generic stones are also covered.
But the meat of the book is in Part II: Magic and Lore, and Part III: The Magic of Metals. These sections describe in detail magical properties of stones, crystals, gems and metals. Each mineral/stone entry include folk names, type of energy, planet, element, associated metals, herbs and/or deities, powers, magical/ritual lore (traditional uses) and magical uses. The last two sections are quite lengthly, describing in detail uses for each stone, and incorporating personal remarks that were actually quite helpful in most cases.
The book is rounded out by tables of correspondences -- elements, planets, purposes, and magical substitutions, as well as a glossary, a nicely annotated bibliography/reading list, and an index. Throughout, Cunningham emphasizes that readers should trust their instincts on what works for them magically, and that many stone magic techniques are subject to the magician's discretion. Recommended.