Brown platy crystals of the extremely rare phosphate mineral wildenauerite from the type and only known locality worldwide in Hagendorf (Hagendorf South Pegmatite, Bavaria, Germany). Ex. Erich Laskowski collection (USA). — Photo: David Hospital · CC BY 4.0
Wildenauerite
Wildenauerite is an IMA-recognized mineral species in the phosphate class, with the chemical formula Zn(Fe³⁺₀.₅Mn²⁺₀.₅)₂Mn²⁺Fe³⁺(PO₄)₃(OH)₃(H₂O)₈.
It crystallizes in the orthorhombic crystal system (space group Pmab). It is a member of the Calcioferrite structural group.
Key properties: specific gravity 2.79; Pearly luster; optically biaxial.
IMA symbol Wda, IMA status: approved, named in 2017.
‘Fingers’ of porous wildenauerite penetrate into rockbridgeite from its surface, as an oxidation product of a precursor, green, mixed-valence iron-bearing species in granitic pegmatite.
It is found associated with Jahnsite-(CaMnFe), strunzite, whitmoreite/earlshannonite, laueite, Zn-bearing rockbridgeite.
The name comes from the old name for the Hagendorf-Süd quarry, Wildenauer-Grube, named for the mining family, Wildenauer.