Observed standard:     U.S.A. pharmacopoeia NF12
Appearance:                White grain or powder
Specificatons:              Item                                   Index 
                                   Main Content                       99.5% 
                                   melting points                      224.5℃-226.5℃
                                   chloride Max                         0.004% 
                                   Sulphate or barium salt Max    0.004%
                                   oxalate or calcium salt Max      0.003%
                                   Fe Max                                4PPM
                                   loss on drying Max                 0.03%
                                   Residua Max                          0.02%
                                   Heavy Metal Max                   6PPM
Package:                     in 25kg net bag.