Iron(II) ($\mathrm{F}{\mathrm{e}}^{2+}$)

The +2 oxidation state of iron; the aqueous cation is commonly represented by $\mathrm{F}{\mathrm{e}}^{2+}$.

The ferrous iodide, supplied in historical solid, syrup and pill preparations.

The ferrous carbonate, used in protected or freshly prepared historical formulations.

The ferrous sulfate; the ordinary 1867 preparation is the heptahydrate.