The Mineralogical Record, Mar/Apr 2003
This third offering in the ExtraLapis English series tackles the complex subject of the tourmaline group of minerals—a subject growing larger and more complex yearly, as mineralogists continue to differentiate into separate species what innocent collectors used to call (and jewelers still call) simply “tourmaline.” Of course, more technical (and much less beautiful) publications are available on the topic, but William Simmons’ chapter here offers a clear overview, with precise formulas and pretty pictures of specimens, of the differences between, say, buergerite, chromdravite, dravite, foitite, liddicoatite, olenite, and povondraite, the brand-new vanadiumdravite—a total of 14 species names as of now. If you want to be told in a relatively painless way why you shouldn’t just say “tourmaline” with a straight face anymore (unless you mean to refer to the mineral group), this is the book for you.
As in the second ExtraLapis English work (the one on emeralds--see above), there is much concern here to enlighten and entertain not only mineral specimen collectors but also those interested in the science of tourmaline and/or in gemstones, gemcutting, and the extensive historical lore of these. The same interwoven style which governs the chapter plan of Emeralds of the World may be seen in a listing of the chapter topics here: the history of tourmaline (both for collectors and professional mineralogists); the chemistry of the tourmaline group; the tourmaline crystal structure (with beautiful cell diagrams); the survey of species (mentioned above); “the crystals of Mr. Vorobiev” (from an early Russian work on Ceylonese tourmalines); the causes of color in tourmalines, leading to two short chapters on slicing liddicoatite to show color zones; “dravite from Qârusulik” (early schorl specimens from Greenland); cuprian elbaite from Paraíba, Brazil; povondraite from Bolivia; a history of Burmese tourmaline; “the Kremlin’s carbuncle” (about a rubellite carving whose story begins in 1570); inclusions, solutions and zoning in elbaite; practical uses of piezoelectric effects in tourmaline; pegmatite geochemistry; and finally a worldwide survey of tourmaline occurrences (the book’s longest chapter: 25 dense pages with, of course, fine color photographs of fine specimens). The general bibliography contains well over 100 entries; and the dedication this time is to Dr. Eugene Edward Foord (1946-1998).
In my opinion it is much to this book’s credit that it includes thorough treatments of somewhat technical matters and of unfamiliar subthemes (e.g. those old, ugly but historical schorls from Greenland) while not devoting extra coverage to better known topics which have been extensively covered elsewhere. For instance, there are no special chapters on the great elbaite finds of California or Maine, the giant gem crystals of the Jonas mine in Brazil, the famous Cruzeiro, Santa Rosa, or other splashy Brazilian occurrences, the classic elbaites from Elba—all these have been generously treated by, among others, the Mineralogical Record. Thus this issue of ExtraLapis English aspires, as does its predecessor on emeralds, to be much more than just an eye-candy recap of what most collectors already know about tourmaline (beg pardon, I mean elbaite); it aspires to fill in the gaps in our general knowledge. So smoothly is this task done that it’s not always easy to tell where main chapter headings, chapter subheadings, and sidebars interface; 16 writers altogether all seem to be talking happily to each other, and we trust them all, especially when we see that among them are illuminati such as Brian C. Cook, Carl Francis, Vandall T. King, John I. Koivula, Ole Petersen and Alfredo Petrov. We are in good hands also, again, with our translators, Al Falster and Günther Neumeier.
Physically the book has all the ExtraLapis virtues we know by now: glossy thick paper, gorgeous color, familiar-to-the-hand magazine size, and a very reasonable price.
-Thomas P. Moore
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