The color of iron(II) chloride ranges from white to pale green. The green hue of this compound is due the presence of the iron ion that has a light green color in the +2 oxidation state, also known as the ferrous ion.
Iron(II) chloride is a compound with the formula FeCl2 that appears in the form of rhombohedral, or hexagonal, crystals that quickly absorb water. In the +2 oxidation state, iron also forms pale yellow solids such as the ferrocyanide ion.
Iron also appears in a +3 oxidation state, in which the ion is called ferric. The ferric ion has a violet color in its hydrated form, but colors solutions in hues ranging from yellow to brown.