Assay of Na min 98.0% Melting point about 970C Chlorine and bromine(Cl) ma 0.002% Sulphur(S) max 0.003% Barium(Ba) max 0.0005% Boron(B) max 0.0005% Calcium(Ca) max 0.001% Lithium(Li) max 0.002% Silver(Ag) max 0.002%