Prussian blue

Synthetic pigment

Prussian blue (also known as Berlin blue, Brandenburg blue, Parisian and Paris blue) is a dark blue pigment produced by oxidation of ferrous ferrocyanide salts. It has the chemical formula Fe4[Fe(CN)6]3. It consists of Fe3+ cations, where iron is in the oxidation state of +3, and [Fe(CN)6]4− anions, where iron is in the oxidation state of +2, so, the other name of this salt is iron(III) hexacyanoferrate(II).

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