The quinary system KCl-K2SO4 MgCl2- MgSO4-Mg(OH)2-H2O and associated systems KCl-K2SO4-Mg(OH)2-H2O and MgCl2-MgSO4-Mg(OH)2-H2O were investigated at 100°. Upon the accomplishment of this quinary system, it was proved that the crystallization field of the new basic triple salt (NS salt B) was so large that various bitterns produced in salt manufacturing factories are included in this field, and it thus became possible to directly separate potassium as sulfate from bittern at 100°
