A term frequently used in connection with conveyors used in gathering
service. The mother conveyor receives coal from other conveyors or
gathering machines, such as shuttle cars, and delivers it to some central
loading point. See also:underground mine conveyor
A name given to a mass of raw quartz, either faced or rough, as found in
nature. Syn:mother
a. N. of Eng. The main roadway to a coal face up which miners travel; air,
power, and supplies pass; and down which coal from the face travels on a
conveyor belt. Trist
b. Eng. The main road of a district off which crossheadings are set away
in longwall working. See also:level; main gate. SMRB
A heavy drag-type or fishtaillike bit having a long grooved shank, the
diameter of which is only slightly less than the width of the cutting
edges; it is designed for drilling boreholes in formations that mud-up
excessively. Long
a. The magmatic rest solution from which a mineral deposit has received
its metal content. Schieferdecker
b. In crystallization, the liquid that remains after the substances
readily and regularly crystallizing have been removed. AGI
a. A main mineralized unit that may not be economically valuable in itself
but to which workable veins are related; e.g., the Mother Lode of
California. CF:master lode
b. An ore deposit from which a placer is derived; the mother rock of a
placer. AGI
See:fusain; mineral charcoal.
See:prase
Iridescent portion of mollusk shells, made of the mineral aragonite.
See also:nacre
A general term for the rock in which a secondary or transported ore
deposit originated; mother lode. AGI
In bituminous coal mining, one who operates the engine that moves an
endless cable by which cars are raised or lowered along an inclined
haulageway. Syn:motioner
See:motion driver
A technical investigation of the essential movements of a worker when
performing a specific task, and assessing the results with the objective
of reducing labor and increasing work performance. The study may also
include the layout tasks, availability of tools or materials, and the
design of new methods. See also:time study
The height of a column of air, of the same density as the air in the
downcast shaft, which exerts a pressure equal to the ventilating pressure.
It is the ventilating pressure expressed in meters of air column. Also
called head. Syn:column; ventilating column. Nelson
An agency (such as water, steam, wind, or electricity) used to impart
motion to machinery. Webster 3rd
In mine subsidence, that portion of the mined strata which, being still in
the process of sinking, goes far to furnish the motive power producing the
phenomena. Briggs
A speed counter, as for a steam engine; also a speedometer.
Crispin
The boxlike portion at the lower end of a coal-cutting machine.
Fay
In mining, a foreperson who directs locomotive (motor) haulage operations
underground and at the surface of a mine. Also called car dispatcher; car
distributor; dispatcher; passing boss; traffic man; train dispatcher.
Syn:turn keeper
In anthracite and bituminous coal mining, a person who in addition to
charging and repairing batteries, removes spent storage batteries from
electric mine locomotives and replaces them with freshly charged ones.
DOT