Appearance

blue-green crystal

Content (FeCl2·4H2O)

≥99.0% 

Insolubles in water

≤0.01%

Sulphate (SO42-)

≤0.003%

Iron of high valence (Fe3+)

≤0.01%

Copper (Cu)

≤0.005%

Alkaline-earth metal 

≤0.1%

Arsenic (As) 

≤0.003%

Zinc(Zn)

≤0.005%

Manganse (Mn)

≤0.07%

Lead (Pb) 

≤0.005%