Vanadinite (Arsenic-bearing) (''Endlichite'')

Item Description

This is an eye-catching old-time specimen of what used to be called "Endlichite" from the famed Erupción Mine in Mexico. I will point of that for some time, "Endlichite" was a valid mineral species, where the substitution of arsenic for vanadium in the crystal structure appeared to be significant enough that it was no longer Vanadinite. Endlichite has since been discredited, and is now classified as an arsenic-bearing variety of Vanadinite. This lovely display specimen hosts dozens of classic, rather lustrous, silvery-brown colored, almost metallic looking, prismatic crystals on matrix. A very graceful and eye-catching specimen, with very little damage on the display side. The largest crystal measures 7 mm. I have not seen anything in way of these specimens (except in old collections), and every good Mexican collection should have a nice "Endlichite" like this in them.
From the collection of Robert (Bob) Reynolds. Bob was a well-known fossil and mineral expert and former Curator of Earth Sciences at the San Bernardino County Museum in California. The rare phyllomanganate-chromate species Reynoldsite was named in his honor in 2011.