Staněkite
Staněkite is an IMA-recognized mineral species in the phosphate class, with the chemical formula Fe³⁺Mn²⁺O(PO₄).
It crystallizes in the monoclinic crystal system (space group I2/a). It is a member of the Wagnerite structural group.
Key properties: Mohs hardness 4–5; specific gravity 3.8; Dark brown streak; Weakly submetallic luster; optically biaxial.
IMA symbol Stk, IMA status: approved, named in 1994.
An uncommon alteration product of earlier phosphates in zoned complex granite pegmatites.
It is found associated with Eosphorite, arrojadite, kryzhanovskite, ferrisicklerite, alluaudite, quartz (Clementine II pegmatite, Namibia); ferrisicklerite, heterosite (Albères, France).
The mineral was named to honor Professor Josef Staněk (1928–), Masarykov University, Brno, Czech Republic, specialist in pegmatite phosphate mineralogy.