Bournonite

Item Description

This iconic thumbnail specimen leaps out to the eye with a 2-cm-tall arrowhead-shaped, mirror lustrous crystal, complete all around, and just perfectly perched upon pyrite matrix. I and many others regard it as among the finest examples of its species in thumbnail size for its unique style, exceptional balance, and 360-degree perfection. While there are many superb bournonites from China, in thumbnail size, they are all completely different from this. It is even different from other Bolivian examples, because of the shape. This, the uniqueness and beauty together, is what elevates a specimen above all the rest. Particularly for a thumbnail, several qualities need to come together just right to make it iconic to the larger mineral world, and this one truly is. What's most important to highlight is the unique morphology of the crystal, it's unlike anything we've seen in Bournonite from anywhere, and we've never seen them again. Typically the Machacamarca crystals are more square or blocky and can form in cogwheels, but if you look closely at Alex's piece, you might actually see a twin line running down the center of the crystal. The specimen is from 2008 finds at the mine that have produced some of the world’s finest Bournonites, although most of them were more typical in shape. There were about 12 specimens in the pocket, and only 3 really good ones with those tapered " arrowhead " shaped crystals (which is notably rare for Bournonite, not only from Bolivia but worldwide). The pocket came out through Brian Kosnar and this was definitely the best in size thumbnail/toenail at the time he acquired it. A few of the specimens were sold to Mike Bergmann, who then sold this to Alex. This has been published in Mineralogical Record, Refined Elegance: The Small Treasures of Mineralogy, November 2022, as a full-page photo (Scovil photo, shown here). We chose to auction this specimen because it is perhaps one of the iconic metallic minerals in the collection and had so many requests. This piece is the little sister to the specimen pictured on the cover of the Mineralogical Record from May-June 2009.