Ferberite, a mineral found in tungstate deposits, is readily found in Asia and Europe but not so readily in the US and Canada. A tungsten mine in Panasqueira, Portugal, has provided excellent samples of ferberite. Ferberite is commonly considered to be part of a three-part, iron-rich group that also contains hubnerite and sanmartinite. Ferberite is characterized by black color, elongated crystals, and dense brittle material.
PANASQUEIRA, PORTUGAL
A surprising number of the world's ...