Calcium ferrocyanide
Calcium ferrocyanide is an inorganic compound with the formula Ca2. It is the Ca2+ salt of 4-, ferrocyanide complex ion. It is insoluble in water, acids, and organic solvents. A yellow solid, it is used as a precursor to the pigment Prussian blue.
Safety
It was listed in 2012 by the EU as a "Food Improvement Agent".In the EU, ferrocyanides were, as of 2018, solely authorised in two food categories as salt substitutes. Kidneys are the organ for ferrocyanide toxicity.