Robusta Coffee On sieve screen 13 90% min Moisture 13% max Foreign matter 0.5% max Black & Broken 5% max Foreign beans 0.1% Robusta Coffee R1 S16 On sieve screen 16 90% min Moisture : 12.5% max Foreign matter : 0.5% max Black & Broken : 2% max Foreign beans: 0.1% Robusta Coffee R1 S18 On sieve screen 18: 90% min Moisture: 12.5% max Foreign matter : 0.5% max Black & Broken 2% max Foreign beans: 0.1%