1897  The top "muck" . . . is, when thawed out, about two-thirds water and one-third sediment.
1959  The searchers moved up to the 600 level and located his body on the rim of the pass beneath about a foot of fine muck.
2n.Hardrock Mining broken rock, either ore or waste.
1960  . . . 150 vertical feet of muck in the stope above had settled gently down over the mule, the string of cars--and our only way out.
1963  Nets claimed that in his heyday he could lift a full shovel of muck with one hand, face the muck car, swing the loaded shovel between his legs, throw the muck up over his hard hat and land it in the car.