Moisture content by weight: maximum 1.5% Total nitrogen content by weight (on dry basis): minimum 18% Neutral ammonium citrate soluble phosphate (as P2O5) content by weight: minimum 46% Water soluble phosphate (as P2O5) content by weight: minimum 41% Particle size: Not less than 90% of the material shall pass through 4 mm IS sieve and be retained on 1 mm IS sieve. Not more than 5% shall be below 1 mm size