Black Tourmaline of Pierrepont, NY

Another wonderful book on a classic New York State mineral location is available.   Many of us have ventured to the Bower Powers Farm in Pierrepont to collect black tourmaline.  We have driven Post Road to the washed out bridge over Leonard Brook, hiked along the brook to the tourmaline laden pits, and collected what we could carry.  But did you ever want to know more about the rich history of the location, the multiple collecting sites, the varied geology, or the complete mineralogy of this classic site?

Well, Steve Chamberlain, along with a host of co-authors (see Full Reference below), has produced a comprehensive review of the location and its treasures that will answer these questions and more that you had not even thought to ask.  The collecting history, which dates to 1859, is detailed in a full chapter complete with the names of the primary discoverers and collectors from nine specific sites/veins scattered on the property.  The complex regional geology relative to the Carthage-Colton Shear Zone that focused mineralizing fluids for a number of our favorite sites is presented at a very understandable level.  The detailed geologic discussion of the tourmaline-rich veins and pods which intrude calc-silicate gneiss and marble host rock truly distinguishes this book from previous descriptions available on this famous St. Lawrence County collecting site.

The black tourmaline and its complex chemistry has led to labels of dravite, uvite, and fluor-uvite and continued confusion about how these wonderfully lustrous terminated crystals should be labeled.  Crystals that have been analyzed typically have a fluor-uvite core and a dravite surface, but a comprehensive evaluation across the many locations on the property has not been undertaken.  After presenting much of the known data, these authors conclude their discussion of this labeling issue with the following sensible suggestion:

“We therefore recommend that unanalyzed specimens of black tourmaline from Pierrepont simply be labeled ‘tourmaline’ as we have done in this volume”

Powers tourmaline: The multi-crystal piece on the left was collected by Mike Walter in 2004 (Figure 199 and also Geologicdesires webpage). The 30mm by 27mm by 13mm crystal on the right is No. 60019 in John Best’s online museum.

But tourmaline is not all one can collect at the Powers site.  And I would be remiss not to acknowledge the full accounting of mineralogy that Chamberlain et. al. have provided. I count 33 different minerals included in the text descriptions among the nine separate locations on the property.  In addition to the ubiquitous tourmaline, terminated quartz, large and well-formed phlogopite biotite, diopside and marialite can all be collected.  Calcite, fluorapatite, titanite, magnetite, and tremolite are available to the informed collector. There are sulfides (pyrite, chalcopyrite, bornite, sphalerite) and their oxidized products (goethite, malachite).  The authors include a section for pseudomorph collectors; uralite (tremolite ps. after diopside) is particularly interesting.  With this book, a collector will know everything that each of the nine sites has yielded.  It is now possible to work towards a full suite of Powers Farm mineralogy on your next visit.

Of course, as a full size Schiffer publication, two other standout features deserve to be mentioned.  First, the text is exquisitely supported by world class photography comparable to the fine cover photo.  There are 223 figures dispersed across 128 pages and most of them depict the tourmaline or other minerals found at the location or field pictures of the locations.  The figures alone are worth the price of the book.  Which brings us to the second feature:  The book is very reasonably priced at $24.95, but with careful online shopping that price can be reduced.

Chamberlain did not write this alone.  The author list includes museum curators, mineralogy/geology professors, and field collectors.  The diversity and knowledge of this experienced group of authors shows in every chapter.  New York mineral collectors will want this book.  Mineral site history buffs will want this book. Tourmaline collectors will want this book.  Every library in the state would be remiss to pass on this one. How about you?

Full reference:

Chamberlain, S. C., Robinson, G. W., Walter, M. R., Chiarenzelli, J. R., Lupulescu, M. V., and Bailey, D. G., 2016, Collector’s Guide to the Black Tourmaline of Pierrepont, New York, Schiffer Publishing Ltd., 128 p.

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