Reviews Gems & Gemology, Spring 2016, Vol. 52, No. 1

Book Review: Collector’s Guide to the Amphibole Group

Collector’s Guide to the Amphibole Group Book Cover
By Robert J. Lauf, softcover, 96 pp., illus., publ. by Schiffer Publishing, Atglen, Pennsylvania, 2015, $19.99.

Collector’s Guide to the Amphibole Group joins a long list of Schiffer Earth Science Monographs authored by Robert Lauf. These individual works focus on a specific mineral group and are intended to bring a greater appreciation of the more technical aspects of the mineralogical sciences to the serious gem and mineral collector, and, perhaps, to remind professional mineralogists of the aesthetic appeal of the minerals they are studying. Given the importance of nephrite jade in the gem industry and the occasional occurrence of gem-quality pargasite, edenite, and richterite, this work should also be of general interest to the practicing gemologist.

The introduction gives a brief discussion of the gemological and industrial uses of various amphibole minerals. The next chapter plunges into the confoundingly complex realm of amphibole taxonomy, crystallography, and crystal chemistry. The difficulty (or impossibility) of finding a simple way to present the naming conventions in the amphibole group quickly becomes apparent. The problem is caused by the ability of the amphibole structure to accept a wide range of atomic substitutions in its crystallographic sites. This, in turn, means that there are an exceedingly large number of ways in which nature can put together atoms to form an amphibole mineral. While much of the information presented here is likely to be technically daunting for many amateur mineralogists and gemologists, if the reader can make it through this section unscathed, he will be rewarded with two much more accessible chapters concerning the geological formation of amphiboles and another chapter which separately covers all of the amphibole species. All of the amphiboles described here are from the very rare species that occur in only one locality, such as joesmithite, to the common examples such as hornblende. Each mineral is described from its initial discovery and naming to the well-known localities to general discussion of typical geological conditions of its formation.

The entire book is perfectly complemented by high-quality images of a multitude of stunning amphiboles. The composition and execution of the mineral and rock photography are, in general, quite exceptional. Unfortunately, far too many of the photos lack field of view measurements or any kind of indication of the size of the specimen.

This work, along with the other monographs in this series, should satisfy the curiosity of serious gem and mineral collectors wanting to understand more about the technical and scientific aspects of their hobby or profession. Perhaps the words of Roberta Oberti in the foreword are relevant when she states her hope that this book can serve as a bridge between the collector and the scientific community.

Aaron Palke is a postdoctoral research associate at GIA in Carlsbad, California