Manganese oxalate is a chemical compound, a salt of manganese and oxalic acid with the chemical formula MnC2O4.

[2][3] The compound creates light pink crystals, does not dissolve in water, and forms crystalline hydrates.

[4] It occurs naturally as the mineral Lindbergite.

[5] Exchange reaction between sodium oxalate and manganese chloride: Manganese oxalate forms light pink crystals.

[6] Crystalline hydrate of the composition MnC2O4•2H2O forms light pink crystals of the orthorhombic system, space group P212121, cell parameters a = 0.6262 nm, b = 1.3585 nm, c = 0.6091 nm, Z = 4, melts in its own crystallization water at 100°C.