Ferberite (twin) with Quartz and Marcasite

Item Description

Here is a wonderful small cabinet specimen of Ferberite from the classic locality at Tasna. This species was sometimes previously referred to as "Wolframite", which was supposed to be an intermediary species between Ferberite and Hubnerite, but has since been discredited. This piece features a predominant crystal at the top of the specimen with the classic, yet unbalanced "butterfly" twinning of Ferberite along the a (100) face. The twin measures 3.1 cm at its longest dimension. The overall quailty of the twin is very good for Tasna, with notably sharp faces, high luster and the classic jet-black color. There are additional smaller bladed crystals of Ferberite on the piece as well, along with many tiny prismatic Quartz crystals and groups of metallic golden Marcasite. 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. 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. It is VERY difficult to obtain MATRIX specimens of twinned Ferberite from Tasna, as most of them are blown off the host rock during the blast. For what it's worth, a few weeks ago in Denver, we saw a dealer with a similar specimen priced at $1500. You don't see many pieces like this one from Tasna, so if you're in the market for a matrix display specimen of Ferberite, don't miss out, these are few and far between.