Halotrichite pseudomorph after Melanterite stalactite (RARE locality specimen)

Item Description

A bizarre and certainly rare specimen from the Anaconda Mine in Butte featuring what was originally a stalactitic group of Melanterite (a hydrated iron sulfate species), that was replaced / pseudomorphed by Halotrichite (a hydrated iron aluminum sulfate species). It's the ONLY example of this material I can ever recall seeing from Butte, and a quick search on mindat.org does not seem to produce any similar specimens, so they must be incredibly rare. It's a big piece, a full large cabinet, and almost gives off the appearance of something organic like coral or even a bone that might have been fossilized. I've never seen anything quite like it, and it would make a superb addition to any Butte suite or a collection of worldwide pseudomorphs, as you rarely see one iron sulfate replacing another like this. Keep in mind that Melanterite is typically found in fibrous efflorescences, though stalactites have been reported, but I had no reference for a stalactitic specimen from Butte prior to this piece.
This piece originally part of the A. E. Seaman Mineral Museum Collection at Michigan Tech.
Ex George Loud Collection No. 5332; 29.7.3.2 MT.1. George (born August 16, 1942) is a well-known mineral collector from Washington, DC and South Carolina respectively, and was a patent lawyer by trade for over 50 years. He assembled one of the great mineral collections in the U.S., comprising worldwide specimens, and in later years he sold the worldwide specimens to focus on minerals of the United States, specifically locality suites with an emphasis on amazing representation of species while still maintaining fine quality. The specimens remarkably range from micros to all the way up to large cabinets in size. We recently acquired most of his impressive 9000+ piece collection, and the VAST majority of these pieces will be offered here in the auctions, as we feel that everyone deserves and equal opportunity at acquiring these important, well-documented and fine quality specimens for their collections.
See: https://mineralogicalrecord.com/biographies_labels/george-loud for more information