Zincostrunzite
Zincostrunzite is an IMA-recognized mineral species in the phosphate class, with the chemical formula ZnFe³⁺₂(PO₄)₂(OH)₂·6.5H₂O.
It crystallizes in the triclinic crystal system (space group P-1). It is a member of the Strunzite structural group.
Key properties: Mohs hardness 2.5; specific gravity 2.66; White streak; Vitreous to silky luster; optically biaxial.
IMA symbol Zstz, IMA status: approved, named in 2016.
Found in zoned phosphatic granitic pegmatite (Hagendorf). In vugs in a secondary phosphate assemblage from altered triplite-zwieselite in wolframite-bearing quartz lens (Sitio do Castelo).
It is found associated with Triplite-zwieselite, fluorapatite, cryptomelane, cacoxenite, plimerite, strengite, strunzite, isokite (Sitio do Castelo).
As the Zn analogue of strunzite.