According to GB/T 26033-2010 Ammonium Metatungstate, ammonium metatungstate is divided into two grades based on different production processes: AMT-P and AMT-J. Among them, AMT-P is the product produced by spray method, with WO3 content generally ≥ 90%; AMT-J is a crystallization process product, with WO3 content generally ≥ 81.5%.
