"Vanuxemite" and Halloysite (ex Rich Kosnar and Pat Gross Collections)

Item Description

There are hundreds of species that occur around the Franklin mining district, and this piece when it was labeled featured what was a valid species at the time, along with a species that might have been misidentified since I cannot find a reference for its occurrence on mindat. Vanuxemite today is defined as an impure Hemimorphite that is probably mixed with Montmorillonite clay. Halloysite is the other species on labeled on this specimen, but I cannot find any current data that states the mineral was ever confirmed to have come from Franklin. According to Palache, "Halloysite has not been found in the district as a distinct mineral but is believed to be a principal constituent of the harsh yellow clay, rich in zinc, that was called "vanuxemite" by Shepard (110). Cross (113) showed that the vanuxemite has the composition of a mixture of equal parts of calamine and halloysite". Bottom line, this is essentially a piece of Franklin "clay", that might have some interest for a Franklin collector. I photographed the piece under the microscope to better show the detail. The piece originally came from the collection of Pat Gross and passed to Rich Kosnar in 1991. I have photographed Pat's hand-written label on the base of her plastic micromount box for reference.