Tennantite-Tetrahedrite Series with Chalcopyrite

Item Description

A rarely seen specimen of the Tennantite-Tetrahedrite Series labeled as coming from the Zilla Mine (Grube Zilla) in the Clausthal-Zellerfeld area of Lower Saxony. The piece was originally labeled as "Fahlerz" in Kurt's collection catalogue, the German name for "Falore", an archaic term used to refer to the Tennantite-Tetrahedrite Series. The catalogue specifically says it's from the Grube Zilla Abt Turm Rosenhof = Zilla Mine, Abbot Tower Rosenhof, which might be a reference to the Rosenhof Mine, which is what we have decided to use at the locality for the specimen. This piece hosts silvery-grey colored tetrahedral crystals of Tennantite-Tetrahedrite which have a partial coating of brassy iridescent Chalcopyrite on certain faces, sitting on matrix. The largest crystal measures 1.7 cm, but it's not complete, smaller undamaged crystals are closer to 1.2 cm on edge. I will point out that the Zilla Mine does not show up on the locality list on mindat.org, but the name is used is both Kurt's collection catalogue, and the label from Wendell Minerals that accompanies the specimen. The Zilla Mine is part of the Rosenhöfer Gangzug mining area. It operated as a separate mine (or shaft) from about 1797 to 1812, and was then consolidated into the Thurm-Rosenhof Mine along with the Braune Lilie and Sankt Johannes mines. Chalcopyrite-coated tetrahedrite on siderite is a classic association from this mine. An interesting oddball locality piece that is certainly from a lesser-known mine.
From the collection of Kurt Hefendehl (#91 D), a well-known German collector all over Europe with worldwide contacts to dealers and collectors. He started collecting seriously at the age of 14 and his great and varied worldwide collection reached over 6000 pieces. He was very active mineralogically until shortly before his passing in 2020 at the age of 82. Considering his collection had a large number of pieces, it still had an unusually high standard of quality from most worldwide localities. He particularly specialized in all classics as well as minerals of the Black Forest, where he spent much time collecting. His Black Forest and German subcollections went to his good friend Wolfgang Wendel. We at The Arkenstone have the privilege of offering the remainder of this great worldwide collection over the next two to three years through our various platforms.