Appearance           

Achromatic or light-yellow clear liquid

Sn2+                   

295-305g/l

Free MSA      

20-85g/l

Specific gravity        

1.500-1.550g/cm3

Cl-                  

50mg/kg  max

Fe                  

15 mg/kg  max 

Zn                  

3 mg/kg  max

Cu                  

4 mg/kg  max

Pb                   

20 mg/kg  max

Content              

51% min

SO42-               

50 mg/kg  max