Ferberite (twin) with Marcasite

Item Description

I can say without fear of contradiction that the finest twinned Ferberite crystals in the world come from Tasna. This piece is a fine quality small that features a classic, "butterfly" twinned crystal of Ferberite showing twinning along the a (100) face. The overall quality of the twin is very good as it has well-defined, sharp faces, good luster and the classic jet-black color. The piece is associated with spherical groups of soft golden metallic Marcasite and no matrix. A second twin can be seen on the right side of the specimen, but you have to look closely to see that there are two distinct crystals there. No major damage on the display side, but it is cleaved on the back where it was separated from the pocket wall. It's incredibly difficult to find these Ferberite twins without a little damage, as they are brittle and cleave easily, especially after a blast during the mining process. Twinned crystals from Bolivia have becoming increasingly difficult to obtain in recent years as the price of tungsten ore has driven the miners to throw all the Ferberite into the crusher, causing thousands of specimens to be lost forever. Priced in the inventory at $950. These twins are definitely the most highly sought after crystal habit from this locality, and are unlike the specimens from well known localities such as Panasqueira, Portugal and Yaogangxian, China, which are just single blades. You don't see many pieces like this one from Tasna, so if you're in the market for a twinned Ferberite, don't miss out as these are few and far between. It should be noted that Ferberite was sometimes previously referred to as "Wolframite", which was supposed to be an intermediary species between Ferberite and Hubnerite, but has since been discredited.