Assay (alkalimetric): ≥ 99.5 %

Identity (IR-spectrum): passes test

Appearance: colorless, deliquescent crystals

Appearance of solution (200 g/l; water): clear and colorless

In water insoluble matter: ≤ 0.01 %

Chloride (Cl): ≤ 10 ppm

Nitrate (NO₃): ≤ 20 ppm

Phosphate (PO₄): ≤ 5 ppm

Sulphate (SO₄): ≤ 200 ppm

Heavy metals (as Pb): ≤ 20 ppm

Cu (Copper): ≤ 5 ppm

Fe (Iron): ≤ 10 ppm

Readily carbonisable substance: passes test

Sulfated ash (600 °C): ≤ 300 ppm