See:clintonite
A former name for clintonite.
A classification of coals based primarily upon the carbon and hydrogen
content calculated to a pure-coal basis, according to the Parr formula.
See also:carbon-hydrogen ratio
a. A connecting link or device for fastening parts together, usually in
such a manner as to permit some motion. Crispin
b. A connecting device for lines and drawbars consisting of a U-shaped
section pierced for cross bolt or a pin. Nichols, 1
c. A short wrought-iron or manganese-steel chain for connecting mine cars
to form a journey or train, for transport by rope haulage or locomotive to
and from the workings. Syn:coupling
Nelson
A person employed to attach and detach the shackles between mine cars
either at a junction near the face or at the pit bottom. Cars are attached
at the junction to form trains for the locomotive or rope haulage. Another
shackler detaches them at the pit bottom for loading into the cage.
Syn:offtake lad
a. Corn. Smooth, round stones on the surface, containing tin ore, and
indicating a vein.
b. See:shoad
a. A color that has been darkened by the addition of black. Hansen
b. A term descriptive of that difference between colors resulting from a
difference in luminosity only, the other color constants being essentially
equal. A darker shade of a color is one that has a lower luminosity.
Hess
A method of showing relief on a map by simulating the appearance of
sunlight and shadows, assuming an oblique light from the northwest so that
slopes facing south and east are shaded (the steeper slopes being darker),
thereby giving a three-dimensional impression similar to that of a relief
model. The method is widely used on topographic maps in association with
contour lines. AGI
a. Region in which refraction effects cause exclusion of echo-ranging
sound signals. Hy
b. An area in which there is little penetration of acoustic waves.
AGI
c. A region 100 degrees to 140 degrees from the epicenter of an earthquake
where, due to refraction from the low-velocity zone inside the core
boundary, there are no direct arrivals of seismic waves.
Syn:blind zone
a. An excavation of limited area compared with its depth; made for finding
or mining ore or coal, raising water, ore, rock, or coal, hoisting and
lowering workers and material, or ventilating underground workings. The
term is often specif. applied to an approx. vertical shaft, as
distinguished from an incline or inclined shaft. A shaft is provided with
a hoisting engine at the top for handling workers, rock, and supplies; or
it may be used only in connection with pumping or ventilating operations..
CF:incline
b. A brick or stone stack or chimney. Standard, 2
c. The upper zone of a blast furnace. Mersereau, 2
d. See:abyss
The difference between the excavation diameter and the finished diameter
in the clear; the extra space allowed to accommodate the permanent shaft
lining. Nelson
See:loop-type pit bottom; pit bottom; single-approach pit bottom.
a. A specially armored cable of great mechanical strength running down the
shaft of a mine. CTD
b. See:borehole cable
The output of ore or coal that can be expected to be raised regularly and
in normal circumstances, per day or week. Nelson
The structure enclosing the top of a shaft designed to prevent short
circuiting of air into or out of the shaft. See also:air lock
BS, 8
A cave formed primarily of a shaft or shafts. AGI
See:collar structure
A useful contrivance for measuring the deformation in the cross section of
a shaft. It consists of a length of 1-1/2-in (3.8-cm) pipe fitted at one
end with a micrometer and at the other end with a hard steel cone. The
micrometer should have a range of 3 to 4 in (7.6 to 10 cm) and should fit
into a bushing in the pipe in some manner. It may thus be removed from the
bar for safe keeping or during transport. Issacson
The drilling of small shafts up to about 5 ft (1.5 m) in diameter with a
shot drill. In Virginia, shafts up to 6 ft (1.8 m) in diameter have been
sunk by core drilling. A ring 4 in (10 cm) wide is formed by roller bits
similar to oilfield rotary drilling. Six tricone cutters are used, and a
large core is formed. A central hole is drilled in the core, and a small
explosive charge is fired to break it for removal. In some cases, it is
removed bodily by a core catcher. Nelson
A cable mounted in a shaft to transmit electrical power to the shaft
bottom and/or to an intermediate level. BS, 13
Scot. The bottom of a shaft.