A miniature but very aesthetic specimen formed by a globular aggregate of pyrite crystals, cubic appearance and striated faces. It is disposed very aerial on a matrix with nice crystals of galena and marcasite.
These mines are located approximately 50 km south of Alnif, near the border with Algeria. This area was already mined in medieval age for the extraction of copper. In the 60s of the last century, French companies expanded shafts and mineral extraction.