Iron (II) Sulphate, also known as ferrous sulphate or -sulfate, is the generic term for a variety of iron salts. It exists in different hydrated forms as FeSO₄∙xH₂O with up to seven water molecules. This heptahydrate is the most common form of iron sulphate and is characterized by its blue-green color. Applications of iron sulphate range from medical purposes, for iron deficiency treatment, to industrial ones. The main industrial application is as a precursor to iron compounds and as a reducing agent. It can also be used as a fertilizer for soil amendment and as a colorant for many different materials. For all these applications a high surface area is essential, which can be achieved by grinding the iron sulphate to the desired particle size on a Bauermeister Roller Mill, Gap Mill or Universal Mill.