Location: Panasqueira Mine, Covilhã, Castelo Branco, Portugal.
Cluster of striated sub euhedral prisms of Arsenopyrite with 4,0 x 3,5 x 2,3cm and 87 grams. Formed in mineralized veins of quartz, sulfides, wolframite, cassiterite, micas, fluorite, carbonates, among others, associated with the generation of a greisen dome by granitic intrusion in Paleozoic schists and graywackes.