Rhodochrosite on Quartz - Colorado classic, Ex. Bill Logan

Item Description

This specimen is part of the 2020 Dallas Mineral Collecting Symposium benefit auction, with proceeds benefiting Mineralogical Record, Rocks & Minerals, Tucson Gem and Mineral Society, and mindat.org. Thanks to all of our participants!

Billing for this auction will occur on Monday, August 24, for payment using PayPal or credit card. Shipping will be billed at cost, or please contact brandy@mineralauctions.com if you'd like to plan on picking up items at future shows or during a stop through Dallas.

Click here for a video of this specimen!

   This rhodochrosite specimen is from one of the very oldest reported localities in Colorado for rhodochrosite. It features a brilliant cherry red rhombohedral crystal sitting on a matrix of crystalline quartz, along with a "drapery" of chalcedony to the left of the major crystal and coating the smaller crystals beneath. Everything about it screams "unusual" compared to the more common localities we all have seen for Colorado rhodochrosite... and the reasoning is obvious! Since this comes from one of the oldest localities, we just seldom see specimens still in existence, as they've either been destroyed or are tucked away in private collections.

   While the name of the mine was not given on the oldest label here, this is no surprise given the earlier days of collecting and dealing in the darkness before the internet and mindat.org. The label is from the well-known San Diego dealer Norm Dawson: see the Mineralogical Record archives at https://mineralogicalrecord.co... for more information and dating of the label to the early 1960s. Further investigation led us to rule out the Sweet Home mine (the quartz is wrong style) and other mines (the chalcedony-like druse of microcrystals is wrong), and narrows the choices really to only a few mines, the Climax or the John Reed. It is gorgeous, and literally glows on a shelf from across the room with a ridiculously saturated color, and is highly translucent. The Climax produced similar specimens but I have seen traces of molybdenite in the matrix and in the rhodo itself, from referencing old specimens with reliable labels. As to this location, I recently had a similar specimen with the EXACT color match and quartz style, from the Kay Robertson collection, and she was both a fanatic for accuracy and a contemporary of Dawson. She also bought her own piece from Dave Wilber in the early 1960s as well. Holding them side by side, you can see they are from the same place (her piece is posted to mindat.org for comparison here: https://www.mindat.org/gallery.php?loctxt=john+reed&min=3406). We also showed the specimen to longtime Colorado collectors without that preface of research, and we got a similar gut answer on sight-ID. So, we can reasonably believe that we have solved the mystery of the exact origin of the specimen, which originally was only labelled as being from a "Gallium mine, Front Range, Colorado." ex Bill Logan Rhodochrosite Collection.

   If interested in learning more, Logan wrote a book on the species called RHODOCHROSITE: Crystals of Drama and Nuance.
If this were actually from the Sweet Home Mine, the site of contemporary (over)production of red rhodochrosite of which much looks more or less the same compared to this unique style, it would be at least valued $9000, if not more. This is a therefore a much more rare and desirable collection piece in the size and price point than any comparably-sized specimen from a more common mine location.
Photos by Jingnan Zhang.
Donation by Arkenstone.