The concept behind this book is that crystals can hold magical power, and that, if properly attuned to a spellcaster, can be used in healing and divination. The 11-page booklet begins and concludes with general discussions of this idea, and how to apply it to a campaign - although it's a logical extension of how crystals feature in some fantasy fiction, it's not necessarily going to work in every campaign setting.

The book includes ten spells, usable by all core spellcasting classes. The spells range from 0 to 4th level for bards, and are generally 1 to 2 levels higher for other classes. All but one of the spells are concerned with either healing or divination, and they're not overpowered, unless, perhaps, your campaign is strong on mystery elements.

The spells are followed by a new cleric domain and sorcerer bloodline, both of which are linked to divination. While written on the assumption that casters use crystals to activate these powers, that could be easily changed for other methods of divination. A wizard speciality follows, which, in this case, boosts magic more generally, with what seems a particularly potent effect at 11th level (although, hey, 11th isn't low...) Finally, there's a monster template, again related to divination.

Something of an oddity of a book, perhaps, but it contains some useful ideas, as well as advice on how best to take advantage of them. Handy, if what you're looking for is divination spells, with a few bits of healing here and there.