Wiktionary
beraunite
n. (context mineral English) A monoclinic-prismatic mineral containing hydrogen, iron, oxygen, and phosphorus.
Wikipedia
Beraunite
Beraunite is an iron phosphate mineral. It was first described by August Breithaupt for an occurrence in Beraun currently in the Czech Republic. Beraunite occurs as a secondary mineral in iron ore deposits, and as an alteration product of primary phosphate minerals in granite pegmatites.
Beraunite crystallizes in the monoclinic crystal system with point group 2/m. Beraunite’s formula is Fe Fe(OH)(PO)·4HO. Aluminium and zinc may substitute in the structure.