nappenative metalsnatural draughtnatural hydrophobicitynatural ventilationnear aperture particlesnearest point rulenegative regulationneritic zonenet slipnet texturenew austrian tunneling methodnine point samplenitnitroglycerinnoble metalsnodenodularnon conductornon polar mineralnonconformitynonel systemnonferrous metalsnonplunging foldnonproductive granitenonproductive mineralizationnonrepresentative samplenonsystematic jointsnonuniform flownormal distributionnormal emissionnormal faultnormal profilenormal separationnuclear explosivesnugget effect