A famous reaction involves treatment with ferric salts to give Prussian blue.
2.
It reacts with ferric salts to form a deep-red ferric thiocyanate complex:
3.
"' Ferric oxalate "', also known as "'iron ( III ) oxalate "', is a chemical compound composed of ferric ions and oxalate ligands; it may also be regarded as the ferric salt of oxalic acid.