RZ46V1: Parallel growths of short prismatic crystals of Arsenopyrite. They are very bright and are slightly coated by small crystals of Siderite and Muscovite.
The sample is with a card from the Folch collection (number 9698) that we'll send to the buyer.
Minas da Panasqueira, Aldeia de São Francisco de Assis, Covilhã, Castelo Branco, Cova da Beira, Centro Region  Portugal (±1966)

Specimen size: 8.5 × 7 × 4.1 cm = 3.35” × 2.76” × 1.61”

Main crystal size: 3 × 2.3 cm = 1.18” × 0.91”