Rock units on either side of an orebody. The hangingwall and footwall rocks of an orebody.
That rock or mineral which must be removed from a mine to keep the mining scheme practical, but which has no value.
Water Gauge (standard U-tube)
Instrument that measures differential pressures in inches of water.
A technique of directing a diamond drill hole in a desired direction away from its current orientation.
A piece of wood tapering to a thin edge and used for tightening in conventional timbering.
Fracturing and lowering of the roof strata at the face as a result of mining operations, as in "taking weight".
A winding machine used for hoisting ore out of a shaft.
The thickness of a lode measured at right angles to the dip.
A device, smaller than a whim, used to raise ore from a shaft.
The excavation, loading, and removal of coal or ore from the ground; winning follows development.
Secondary or tertiary vertical or near-vertical opening sunk from a point inside a mine for the purpose of connecting with a lower level or of exploring the ground for a limited depth below a level.
A steel wire rope used for winding in shafts and underground haulages. Wire ropes are made from medium carbon steels. Various constructions of wire rope are designated by the number of strands in the rope and the number of wires in each strand. The following are some common terms encountered: airplane strand; cablelaid rope; cane rope; elevator rope; extra-flexible hoisting rope; flat rope; flattened-strand rope; guy rope; guy strand; hand rope; haulage rope; hawser; hoisting rope; lang lay rope; lay; left lay rope; left twist; nonspinning rope; regular lay; reverse-laid rope; rheostat rope; right lay; right twist; running rope; special flexible hoisting rope; standing rope; towing hawser; transmission rope.
A claim post placed on a claim line when it cannot be placed in the corner of a claim because of water or difficult terrain.
The liquid resources a company has to meet day-to-day expenses of operation; defined as the excess of current assets over current liabilities.
Any place in a mine where material is extracted during a mining cycle.
From the outby side of the last open crosscut to the face.
The entire system of openings in a mine for the purpose of exploitation.
Amounts deducted from a company's reported profit for depreciation or preproduction costs. Writeoffs are not an out-of-pocket expense, but reduce the amount of taxable profit.