a. An orthorhombic mineral, PbCuBiS3 ; sp gr, 6.1 to 6.8; an ore of
lead, copper, and bismuth. Syn:acicular bismuth; aciculite; needle ore;
acicular bismuth; aciculite.
b. Wolframite pseudomorphous after scheelite.
See:hemafibrite
American Institute of Mining and Metallurgical Engineers.
Statistical Research Bureau
a. The mixture of gases that surrounds the Earth and forms its atmosphere;
composed by volume of 21% oxygen and 78% nitrogen; by weight about 23%
oxygen and 77% nitrogen. It also contains about 0.03% carbon dioxide, some
aqueous vapor, argon, and other gases. Hartman, 1
b. The current of atmospheric air circulating through and ventilating the
workings of a mine.
c. Atmospheric air delivered under compression to bottom of drill hole
through the drill stem and used in place of water to clear the drill bit
of cuttings and to blow them out of the borehole. Long
d. Air piped under compression to work areas and used to operate drilling
or mining machinery. See also:air circulation
See:hemafibrite
A surface that seems to prefer contact with air to contact with water. A
particle (or mineral) of this sort will adhere to an air bubble and float
out of a flotation pulp; otherwise, the particle will not float. Also
called water-repellent surface; hydrophobic. CF:water-avid surface
Newton, 1
The division of an opening in a mine by an airtight wall into two sides;
one side is used as an air intake, the other side as a return.
In froth flotation, the small air pocket inducted or forced into the pulp
at depth; e.g., bell and the two-walled semistable bubble after emergence
from pulp into froth have different characteristics and gas-to-liquid,
area-to-volume relationships, hence the distinction. These bubbles vary in
attractive and retaining power for aerophilic grains and are a critical
component of the flotation process. Syn:air bubble
In a cupola furnace, an annular air space around the furnace, from which
air is forced into the furnace. Henderson
a. A term improperly used by some diamond drillers as a syn. for air
circulation. See also:air circulation
b. A disturbance in underground workings accompanied by a strong rush of
air. The rush of air, at times explosive in force, is caused by the
ejection of air from large underground openings, the sudden fall of large
masses of rock, the collapse of pillars, slippage along a fault, or a
strong current of air pushed outward from the source of an explosion.
Long
A method of blasting in which compressed air at very high pressure is
piped to a steel shell in a shot hole and discharged. BS, 12
Air trapped in the upper end of an unvented inner tube of a double-tube
core barrel, which, when sufficiently compressed, acts like a solid and
stops further advance of core into the inner tube. Syn:air cushion
Long
airborne electromagnetic prospecting
Electromagnetic surveys carried out with airborne instruments.
Dobrin
An instrument used to measure variations in the Earth's magnetic field
while being transported by an aircraft. See also:magnetometer
AGI
a. A rectangular wooden pipe or tube made in lengths of 9 to 15 ft (2.7 to
4.6 m) for ventilating a heading or a sinking shaft. Fay
b. A box for holding air. Fay
c. The conduit through which air for heating rooms is supplied to a
furnace. Standard, 2
A method of breaking down coal by the use of high-pressure compressed air.
McAdam, 2
A hollow or pierced brick built into a wall to allow the passage of air.
A passage through which a ventilating current is conducted over an entry
or air course; an overcast. See also:air crossing
See:air bell
A vessel installed on piston pumps to minimize the pulsating discharge of
the liquid pumped. The chamber contains air under pressure and is fitted
with an opening on its underside into which some of the liquid from the
pump is forced upon the delivery stroke of the piston. The air acts as a
cushion to lessen the fluctuation of the liquid flow between the suction
and delivery strokes of the piston. Crispin