Assay (acidimetric): ≥ 98.0 %

Identity: passes test

Insoluble matter: ≤ 50 ppm

Heavy metals (as Pb): ≤ 50 ppm

Total nitrogen (N): ≤ 20 ppm

Chloride (Cl): ≤ 10 ppm

Nitrate (NO₃): ≤ 5 ppm

As (Arsenic): ≤ 200 ppm

Ca (Calcium): ≤ 50 ppm

Cd (Cadmium): ≤ 5 ppm

Co (Cobalt): ≤ 5 ppm

Cu (Copper): ≤ 5 ppm

Fe (Iron): ≤ 10 ppm

K (Potassium): ≤ 20 ppm

Mg (Magnesium): ≤ 10 ppm

Mn (Manganese): ≤ 5 ppm

NH₄ (Ammonium): ≤ 10 ppm

Na (Sodium): ≤ 50 ppm

Ni (Nickel): ≤ 5 ppm

Pb (Lead): ≤ 5 ppm

Sb (Antimony): ≤ 10 ppm

Zn (Zinc): ≤ 5 ppm

Reducing matter (P₂O₃): ≤ 0.01 %

Corresponds to ACS,ISO,Reag. Ph Eur