Banding in color and composition of ores caused by diffusion. AGI
See:ilvaite
A slide wire or cable extending from a work platform in a drill tripod or
derrick at an oblique angle downward to an anchor on the ground, which the
derrick or tripod worker could grasp and use when sliding to safety in an
emergency. Long
The time in which, through the employment of the available capital, the
ore reserves--or such reasonable extension of the ore reserves as
conservative geological analysis may justify--will be extracted.
Hoover
Theoretically, the mineral or coal reserves divided by the actual or
projected average annual production. Nelson
a. The vertical height traveled by a cage in a shaft. Fay
b. The distance between the first level and the surface or between any two
levels. Fay
c. Any of the various gangways from which coal is raised at a slope
colliery. Fay
d. A certain thickness of coal worked in one operation. Fay
e. To break up, bench, or blast coal from the bottom of the seam upward.
Fay
f. The plane approx. parallel with the floor of the quarry, along which
the stone is usually split in quarrying. Fay
g. The quantity of ore between one haulage level and the next above or
below. Nelson
h. A step or bench in a multiple layer excavation. Nichols, 1
i. The amount a bit is raised off the bottom of a drill hole by excessive
pressure created by pump surges or the forcing of too great a volume of
circulation fluid through the bit. Long
j. In churn drilling, the vertical movement of the drill tools while
drilling. Long
k. In pumping, the difference in the elevation between the surface of the
liquid being pumped and the elevation at which the pump stands or the
elevation at which the liquid is discharged. Long
l. A certain vertical thickness of coal seams and measures, having
considerable inclination, between or in which the workings are being
carried on to the rise, all the coal being raised from one shaft bottom.
Fay
m. The upheaval of the floor in coal mines. See also:creep
Nelson
n. The extraction of a coal pillar in lifts or slices. See also:jud
Nelson
a. In mining, a shothole drilled near the floor when tunneling and fired
subsequently to the cut and relief holes. Pryor, 3
b. See:core lifter
c. In ore grinding, a projection, rib or wave profile on the horizontal
liners (body liners) of a ball, tube, or rod mill, designed to aid the
crop load in the mill to rise. In a drum-washer or dense-medium separator,
a perforated plate, projecting radially inward from the circumference of a
horizontal cylindrical vessel, used to stir, lift, or remove material.
Pryor, 3
Shotholes drilled along the floor of a tunnel for lifting the rock to
floor level. They are fired after the cut holes, or by delay detonators in
the round. Nelson
See:lifter holes
See:core lifter
A lock gate that is raised vertically to open. Hammond
See:tilt hammer
Scot. Drawing hutches or cars out of the working places into the main
roads. Fay
An arrangement of pulleys and rope that enables heavy weights to be lifted
with least effort. Hammond
a. The weight that the hydraulic cylinders in the swivel head of a diamond
drill can raise or lift. Long
b. See:drill capacity
Fencing placed around the mouth of a shaft, and lifted out of the way by
the ascending cage. Fay
An electromagnet that is hung from a crane and used instead of a hook for
lifting iron or steel components. Hammond
A series of pumps or sets of pumps by which water is lifted from the mine
in successive stages. See:lift
S. of Wales. See:lifting guard
A horizontal tension fracture observed in massive rocks, such as granite;
thought to originate from the removal of load in quarrying.
CF:sheeting
A pump for lifting to its own level, as distinguished from a force pump. A
suction pump. Also called bucket pump. See also:suction head
Standard, 2; Fay