FERBERITE with ARSENOPYRITE and PYRITE

SPECIMEN DESCRIPTION

Panasqueira mine in Castelo Branco District, Portugal is one of Europe's most important tin-tungsten mines, having started way back in 1896 and reaching a peak in WW2 with 10,000 workers. The mine is still operating, but on a much smaller scale. Ferberite (iron tungstate) is the main ore of tungsten produced and can form very large bladed crystals. This cabinet-sized specimen shows the scale of the biggest crystals, with black, resinous, bladed crystals to 7 cm in length and 7.3 cm wide. It also highlights the remarkable density of tungsten, the sixth densest metal, even denser than gold. The Ferberite crystals on this specimen form in parallel alignment, with classic vertical growth lines and chisel-shaped terminations. Their overall shape, or form is very fine, although with the partial overgrowth of Muscovite on the front, and Arsenopyrite and Pyrite on the rear, the crystals are not quite perfection. There is also a chipped corner to the upper right hand crystal. Nevertheless, it presents extremely well the high quality large Ferberite crystals from this classic European occurrence and an area of bright silvery Arsenopyrite crystals at the base at the front sets it off really well. With support, it displays very well in an upright position. A classic from Panasqueira mine.