Home Return Button

This book sets the gold standard for those who want to know the bottom line how the agates, jaspers, and opals form and how to identify and classify them. It is a Southwestern U.S. field guide to the identification of the agates, jaspers, and opals, and their inclusions. It includes the complete geology and geochemistry of their formation and the formation of their inclusions. It also has a complete classification Lexicon of over 570 silicate species and inclusions with extensive sample photographs. The book covers models of formation and documents common myths about these silicates. It presents over 560 conjectures (theories) of how the agates, jaspers, and opals form.


A very appreciated addition to the agate literature.

I appreciate your book and the enormous value of its facts and observations.

Dr. Jens Goetze, Professor of Mineralogy

University of Freiberg, Germany


In my opinion your book gives the best and most comprehensive coverage on silica minerals I have read. I really like to read it. It references all the relevant studies and explains them thoroughly and critically.

Dr. Kari Kinnunen

The Geological Survey of Finland




Home Return Button