The mineral pyrite, or iron pyrite, also known as fool’s gold, is an iron sulfide with the chemical formula FeS2 (iron(II) disulfide). Pyrite is considered the most common of the sulfide minerals.
This piece is form the well know Victoria Mine, Navajún, Spain. The mine-quarry is exploited to obtain pyrite only for collection and decoration. It is located 2.4 km to the NNW of Navajún, and you can access it via a track that begins in Navajún (near Cervera del Río Alhama).