... use for irrigation 2 use for industry 3 potassium fertilizer Potassium Nitrate tech grade 13-0-46Molecular Formula: KNO3,Molecular Weight:101.1, ... Appearance: white crystal,Assay:99% min, N:13% min, K2O:46 ... by itself, it has an NPK rating of 13-0-45. Potassium nitrate is also one of the three components of black ...