Pale green crystals of ludlamite associated to brown phosphoferrite. From: Hagendorf, Oberpfalz, Bavaria, Germany. — Photo: David Hospital · CC BY-SA 4.0
Phosphoferrite
Phosphoferrite is an IMA-recognized mineral species in the phosphate class, with the chemical formula Fe²⁺₃(PO₄)₂·3H₂O.
It crystallizes in the orthorhombic crystal system (space group Pbna). It is a member of the Reddingite structural group.
Key properties: Vitreous to subresinous luster; optically biaxial.
IMA symbol Phf, IMA status: approved, named in 1920.
An alteration product of triphylite in zoned complex granite pegmatites.
It is found associated with Ludlamite, vivianite, hureaulite, lithiophilite, siderite.
The name refers to PHOSPHOrus and iron, FERRum, in the composition. Type Material: National Museum of Natural History, Washington, D.C., USA, 150230.