Sodium cupriferrocyanide, Na₂CuFe(CN)₆

Sodium cupriferrocyanide, Na₂CuFe(CN)₆, is prepared by boiling solutions of cupric salts and sodium ferrocyanide, and by boiling cupric ferrocyanide with sodium ferrocyanide and, after filtering, allowing the clear solution to evaporate in air.1 It yields lustrous brown crystals, insoluble in cold water, but decomposed when boiled with water, dilute acids, or alkalies.