Arsentsumebite ps. Mimetite, Malachite ps. Azurite (circa 1910)

Item Description

Found long ago in the great Tsumeb Mine's oldest, upper oxidation zone (prior to WWI, generally said to be from early 1900s to 1910 or so), this is a very rare pseudomorph of Arsentsumebite which is a replacement pseudomorph after Mimetite, in that it has replaced the original crystals with fidelity to form. This is also the TYPE LOCALITY (first described location found) for the mineral. Many of these vibrant-green Arsentsumebites are hollow, as seen on the exposed ends of the crystals where you can look down the C-axis. For contrast: Rising up within this forest of crystals is a sharp, pillow-shaped, 1.6 cm Malachite after Azurite pseudomorph that still has exposed blue Azurite peeking out from the variegated green surface. The contrast in forms is really attractive, and makes the piece all the more aesthetic and interesting. There are also numerous, small, gemmy, tabular crystals of lustrous wulfenite, or maybe also a few cerussite mixed in. Early on, there had been some thought that some of the green might be Bayldonite, but that tends to be a darker shade of green. Quality specimens of this classic material, let alone with these combinations, are exceedingly difficult to find. The sharp features and three-dimensionality make this old-time piece unusually display-worthy. Note the old label confusing the crystal shape with pyromorphite, as arsentsumebite was an unknown species at the time! Such specimens usually ONLY have the arsen pseudos...here, the other associations add a rich depth characteristic of Tsumeb.