NASICON-related Na₃.₄Mn₀.₄Fe₁.₆(PO₄)₃.

The solid solution, sodium [iron(III)/manganese(II)] tris-(orthophosphate), Na₃.₄Mn₀.₄Fe₁.

KMg(0.09)Fe(1.91)(PO(4))(2).

KMg(0.09)Fe(1.91)(PO(4))(2), potassium [iron(II)/magnesium] iron(III) bis(orthophosphate), is a solid solution derived from compounds with general formula KM(II)Fe(PO(4))(2) (M(II) = Fe, Cu), in which the Mg atoms substitute Fe atoms only in the octa-hedrally surrounded sites.